moving huge part of code out of check into new module checkFunctionBodies

git-svn-id: https://svn.cs.ru.nl/repos/clean-compiler/trunk@272 1f8540f1-abd5-4d5b-9d24-4c5ce8603e2d

6 files changed, 2075 insertions, 1975 deletions

diff --git a/frontend/check.dcl b/frontend/check.dcl
index 8f482e0..125d4a4 100644
--- a/frontend/check.dcl
+++ b/frontend/check.dcl
@@ -7,11 +7,7 @@ cPredefinedModuleIndex 		:== 1
 checkModule :: !ScannedModule !IndexRange ![FunDef] !Int !Int !(Optional ScannedModule) ![ScannedModule] !{#DclModule} !{#FunDef} !*PredefinedSymbols !*SymbolTable !*File !*Heaps
 	-> (!Bool, !*IclModule, *{# DclModule}, *{! Group}, !(Optional {# Index}), !.{#FunDef},!Int, !*Heaps, !*PredefinedSymbols, !*SymbolTable, *File)
 
-retrieveGlobalDefinition :: !SymbolTableEntry !STE_Kind !Index -> (!Index, !Index)
-
-newFreeVariable :: !FreeVar ![FreeVar] ->(!Bool, ![FreeVar])
-
-convertIndex :: !Index !Index !(Optional ConversionTable) -> !Index
+checkFunctions :: !Index !Level !Index !Index !*{#FunDef} !*ExpressionInfo !*Heaps !*CheckState -> (!*{#FunDef}, !*ExpressionInfo, !*Heaps, !*CheckState)
 
 determineTypeOfMemberInstance :: !SymbolType ![TypeVar] !InstanceType !Specials !*TypeHeaps -> (!SymbolType, !Specials, !*TypeHeaps)
 
diff --git a/frontend/check.icl b/frontend/check.icl
index d802c46..f806379 100644
--- a/frontend/check.icl
+++ b/frontend/check.icl
@@ -2,8 +2,8 @@ implementation module check
 
 import StdEnv
 
-import syntax, typesupport, parse, checksupport, utilities, checktypes, transform, predef //, RWSDebug
-import explicitimports, comparedefimp
+import syntax, typesupport, parse, checksupport, utilities, checktypes, transform, predef
+import explicitimports, comparedefimp, checkFunctionBodies
 
 cPredefinedModuleIndex 	:== 1
 
@@ -11,39 +11,8 @@ isMainModule :: ModuleKind -> Bool
 isMainModule MK_Main	= True
 isMainModule _ 			= False
 
-convertIndex :: !Index !Index !(Optional ConversionTable) -> !Index
-convertIndex index table_index (Yes tables)
-	= tables.[table_index].[index]
-convertIndex index table_index No
-	= index
-	
-getPredefinedGlobalSymbol :: !Index !Index !STE_Kind !Int !*CheckState -> (!Global DefinedSymbol, !*CheckState)
-getPredefinedGlobalSymbol symb_index module_index req_ste_kind arity cs=:{cs_predef_symbols,cs_symbol_table}
-	# (pre_def_mod, cs_predef_symbols)	= cs_predef_symbols![module_index]
-	# mod_id							= pre_def_mod.pds_ident
-	# (mod_entry, cs_symbol_table)		= readPtr mod_id.id_info cs_symbol_table
-	| mod_entry.ste_kind == STE_ClosedModule
-		# (glob_object, cs) = get_predefined_symbol symb_index req_ste_kind arity mod_entry.ste_index
-										{ cs & cs_predef_symbols = cs_predef_symbols, cs_symbol_table = cs_symbol_table}
-		= ({ glob_object = glob_object, glob_module = mod_entry.ste_index }, cs)
-		= ({ glob_object = { ds_ident = { id_name = "** ERRONEOUS **", id_info = nilPtr }, ds_index = NoIndex, ds_arity = arity }, glob_module = NoIndex},
-				  		{ cs & cs_error = checkError mod_id "not imported" cs.cs_error, cs_predef_symbols = cs_predef_symbols, cs_symbol_table = cs_symbol_table })
-where
-	get_predefined_symbol :: !Index !STE_Kind !Int !Index !*CheckState -> (!DefinedSymbol,!*CheckState)
-	get_predefined_symbol symb_index req_ste_kind arity mod_index cs=:{cs_predef_symbols,cs_symbol_table,cs_error}
-		# (pre_def_symb, cs_predef_symbols)	= cs_predef_symbols![symb_index]
-		  symb_id							= pre_def_symb.pds_ident
-		  (symb_entry, cs_symbol_table) 	= readPtr symb_id.id_info cs_symbol_table
-		  cs = { cs & cs_predef_symbols = cs_predef_symbols, cs_symbol_table = cs_symbol_table }
-		| symb_entry.ste_kind == req_ste_kind
-			= ({ ds_ident = symb_id, ds_index = symb_entry.ste_index, ds_arity = arity }, cs)
-			= case symb_entry.ste_kind of
-				STE_Imported kind module_index
-					| mod_index == module_index && kind == req_ste_kind
-						-> ({ ds_ident = symb_id, ds_index = symb_entry.ste_index, ds_arity = arity }, cs)
-				_
-					-> ({ ds_ident = symb_id, ds_index = NoIndex, ds_arity = arity }, { cs & cs_error = checkError symb_id "undefined" cs.cs_error })
-		
+
+
 checkTypeClasses :: !Index !Index !*{#ClassDef} !*{#MemberDef} !*{#CheckedTypeDef} !*{#DclModule} !*TypeHeaps !*CheckState
 	-> (!*{#ClassDef}, !*{#MemberDef}, !*{#CheckedTypeDef}, !*{#DclModule}, !*TypeHeaps, !*CheckState)
 checkTypeClasses class_index module_index class_defs member_defs type_defs modules type_heaps=:{th_vars} cs=:{cs_symbol_table,cs_error}
@@ -486,560 +455,6 @@ where
 			= (tc_types, checkError ds_ident.id_name "illegal specialization" error)
 			= (tc_types, error)
 
-/*
-retrieveSelectorIndexes mod_index {ste_kind = STE_Selector selector_list, ste_index, ste_previous }
-	# imported_selectors = retrieveSelectorIndexes mod_index ste_previous
-	= mapAppend (\ sel -> { sel & glob_module = mod_index }) selector_list [{glob_module = mod_index, glob_object = ste_index } : imported_selectors ]
-retrieveSelectorIndexes mod_index {ste_kind = STE_Imported (STE_Selector selector_list) dcl_mod_index, ste_index }
-	= [ { glob_object = ste_index, glob_module = dcl_mod_index } : selector_list ]
-retrieveSelectorIndexes mod_index off_kind
-	= []
-*/
-
-retrieveSelectorIndexes mod_index {ste_kind = STE_Selector selector_list, ste_index, ste_previous }
-	= map (adjust_mod_index mod_index) selector_list
-where
-	adjust_mod_index mod_index selector=:{glob_module}
-		| glob_module == NoIndex
-			= { selector & glob_module = mod_index }
-			= selector
-retrieveSelectorIndexes mod_index off_kind
-	= []
-
-checkFields :: !Index ![FieldAssignment] !(Optional Ident) !u:ExpressionInfo !*CheckState
-	-> (!Optional ((Global DefinedSymbol), Index, [Bind ParsedExpr (Global FieldSymbol)]), !u:ExpressionInfo, !*CheckState)
-checkFields mod_index field_ass opt_type e_info=:{ef_selector_defs,ef_type_defs,ef_modules} cs
-	# (ok, field_ass, cs) = check_fields field_ass cs
-	| ok
-		# (opt_type_def, ef_selector_defs, ef_type_defs, ef_modules, cs)
-				= determine_record_type mod_index opt_type field_ass ef_selector_defs ef_type_defs ef_modules cs
-		  e_info = { e_info & ef_selector_defs = ef_selector_defs, ef_type_defs = ef_type_defs, ef_modules = ef_modules}
-		= case opt_type_def of
-			Yes ({td_index,td_rhs = RecordType {rt_constructor,rt_fields}}, type_mod_index)
-				# (field_exprs, cs_error) = check_and_rearrange_fields type_mod_index 0 rt_fields field_ass cs.cs_error
-				-> (Yes ({ glob_object = rt_constructor, glob_module = type_mod_index }, td_index, field_exprs), e_info, { cs & cs_error = cs_error })
-			Yes _
-				# (Yes type_ident) = opt_type
-				-> (No, e_info, { cs & cs_error = checkError type_ident "not a record constructor" cs.cs_error })
-			No
-				-> (No, e_info, cs)
-		= (No, e_info, cs)
-where
-
-	check_fields [ bind=:{bind_dst} : field_ass ] cs=:{cs_symbol_table,cs_error}
-		# (entry, cs_symbol_table) = readPtr bind_dst.id_info cs_symbol_table
-		# fields = retrieveSelectorIndexes mod_index entry 
-		| isEmpty fields
-			= (False, [], { cs & cs_symbol_table = cs_symbol_table, cs_error = checkError bind_dst "not defined as a record field" cs_error })
-			# (ok, field_ass, cs) = check_fields field_ass { cs & cs_symbol_table = cs_symbol_table }
-			= (ok, [{bind & bind_dst = (bind_dst, fields)} : field_ass], cs)
-	check_fields [] cs
-		= (True, [], cs)
-
-	try_to_get_unique_field []
-		= No
-	try_to_get_unique_field [ {bind_dst = (field_id, [field])} : fields ]
-		= Yes field
-	try_to_get_unique_field [ _ : fields ]
-		= try_to_get_unique_field fields
-	
-	determine_record_type mod_index (Yes type_id=:{id_info}) _ selector_defs type_defs modules cs=:{cs_symbol_table, cs_error}
-		# (entry, cs_symbol_table) = readPtr id_info cs_symbol_table
-		# (type_index, type_mod_index) = retrieveGlobalDefinition entry STE_Type mod_index
-		| type_index <> NotFound
-			| mod_index == type_mod_index
-			 	# (type_def, type_defs) = type_defs![type_index]
-			 	= (Yes (type_def, type_mod_index), selector_defs, type_defs, modules, { cs & cs_symbol_table = cs_symbol_table })
-				# (type_def, modules) = modules![type_mod_index].dcl_common.com_type_defs.[type_index]
-				= (Yes (type_def, type_mod_index), selector_defs, type_defs, modules, { cs & cs_symbol_table = cs_symbol_table })
-			= (No, selector_defs, type_defs, modules, { cs & cs_error = checkError type_id " not defined" cs_error, cs_symbol_table = cs_symbol_table})
-	determine_record_type mod_index No fields selector_defs type_defs modules cs=:{cs_error}
-		# succ = try_to_get_unique_field fields
-		= case succ of
-			Yes {glob_module, glob_object}
-				| glob_module == mod_index
-					# (selector_def, selector_defs) = selector_defs![glob_object]
-					  (type_def, type_defs) = type_defs![selector_def.sd_type_index]
-					-> (Yes (type_def, glob_module), selector_defs, type_defs, modules, cs)
-					# ({dcl_common={com_selector_defs,com_type_defs}}, modules) = modules![glob_module]
-					# selector_def = com_selector_defs.[glob_object]
-					  type_def = com_type_defs.[selector_def.sd_type_index]
-					-> (Yes (type_def,glob_module), selector_defs, type_defs, modules, cs)
-			No
-				-> (No, selector_defs, type_defs, modules, { cs & cs_error = checkError "" " could not determine the type of this record" cs.cs_error })
-
-	check_and_rearrange_fields :: Int Int {#FieldSymbol} ![Bind ParsedExpr (Ident,[Global .Int])] *ErrorAdmin -> ([Bind ParsedExpr .(Global FieldSymbol)],!.ErrorAdmin);
-	check_and_rearrange_fields mod_index field_index fields field_ass cs_error
-		| field_index < size fields
-			# (field_expr, field_ass) = look_up_field mod_index fields.[field_index] field_ass
-		 	  (field_exprs, cs_error) = check_and_rearrange_fields mod_index (inc field_index) fields field_ass cs_error
-			= ([field_expr : field_exprs], cs_error)
-		| isEmpty field_ass
-			= ([], cs_error)
-			= ([], foldSt field_error field_ass cs_error)
-
-	where			
-		look_up_field mod_index field []
-			= ({bind_src = PE_WildCard,  bind_dst = { glob_object = field, glob_module = mod_index }}, [])
-		look_up_field mod_index field=:{fs_index} [ass=:{bind_src, bind_dst = (_, fields)} : field_ass]
-			| field_list_contains_field mod_index fs_index fields
-				= ({bind_src = bind_src, bind_dst = { glob_module = mod_index, glob_object = field}}, field_ass)
-				# (field_expr, field_ass) = look_up_field mod_index field field_ass
-				= (field_expr, [ass : field_ass])
-
-		field_list_contains_field mod_index fs_index []
-			= False
-		field_list_contains_field mod_index fs_index [{glob_object,glob_module} : fields]
-			= mod_index == glob_module && fs_index == glob_object || field_list_contains_field mod_index fs_index fields
-
-		field_error {bind_dst=(field_id,_)} error
-			= checkError field_id " field is either multiply used or not a part of this record" error
-
-::	ExpressionInfo =
-	{	ef_type_defs		:: !.{# CheckedTypeDef}
-	,	ef_selector_defs	:: !.{# SelectorDef}
-	,	ef_cons_defs		:: !.{# ConsDef}
-	,	ef_member_defs		:: !.{# MemberDef}
-	,	ef_class_defs		:: !.{# ClassDef}
-	,	ef_modules			:: !.{# DclModule}
-	,	ef_is_macro_fun		:: !Bool
-	}
-
-::	ExpressionState =
-	{	es_expr_heap	:: !.ExpressionHeap
-	,	es_var_heap			:: !.VarHeap
-	,	es_type_heaps		:: !.TypeHeaps
-	,	es_calls			:: ![FunCall]
-	,	es_dynamics			:: ![ExprInfoPtr]
-	,	es_fun_defs			:: !.{# FunDef}
-	}
-	
-::	ExpressionInput =
-	{	ei_expr_level	:: !Level
-	,	ei_fun_index	:: !Index
-	,	ei_fun_level	:: !Level
-	,	ei_mod_index	:: !Index
-//	,	ei_fun_kind		:: !FunKind
-	}
-
-cIsInExpressionList		:== True
-cIsNotInExpressionList	:== False
-
-::	UnfoldMacroState =
-	{	ums_var_heap	:: !.VarHeap
-	,	ums_modules		:: !.{# DclModule}
-	,	ums_cons_defs	:: !.{# ConsDef}
-	,	ums_error		:: !.ErrorAdmin
-	}
-
-unfoldPatternMacro mod_index macro_index macro_args opt_var ps=:{ps_var_heap, ps_fun_defs} modules cons_defs error
-	# (macro, ps_fun_defs) = ps_fun_defs![macro_index]
-	= case macro.fun_body of
-		TransformedBody {tb_args,tb_rhs}
-			| no_sharing tb_args
-				# ums = { ums_var_heap = fold2St bind_var tb_args macro_args ps_var_heap, ums_modules = modules, ums_cons_defs = cons_defs, ums_error = error }
-				  (pattern, {ums_var_heap,ums_modules,ums_cons_defs,ums_error}) = unfold_pattern_macro mod_index macro.fun_symb opt_var tb_rhs ums
-				-> (pattern, { ps_fun_defs = ps_fun_defs, ps_var_heap = ums_var_heap}, ums_modules, ums_cons_defs, ums_error)
-				-> (AP_Empty macro.fun_symb, { ps_fun_defs = ps_fun_defs, ps_var_heap = ps_var_heap},
-						modules, cons_defs, checkError macro.fun_symb " sharing not allowed" error)
-		_
-			-> (AP_Empty macro.fun_symb, { ps_fun_defs = ps_fun_defs, ps_var_heap = ps_var_heap},
-					modules, cons_defs, checkError macro.fun_symb " illegal macro in pattern" error)
-	
-where
-	no_sharing [{fv_count} : args]
-		= fv_count <= 1 && no_sharing args
-	no_sharing []
-		= True
-	
-	bind_var {fv_info_ptr} pattern ps_var_heap
-		= ps_var_heap <:= (fv_info_ptr, VI_Pattern pattern)
-
-	unfold_pattern_macro mod_index macro_ident _ (Var {var_name,var_info_ptr}) ums=:{ums_var_heap}
-		# (VI_Pattern pattern, ums_var_heap) = readPtr var_info_ptr ums_var_heap
-		= (pattern, { ums & ums_var_heap = ums_var_heap})
-	unfold_pattern_macro mod_index macro_ident opt_var (App {app_symb,app_args}) ums
-		= unfold_application  mod_index macro_ident opt_var app_symb app_args ums
-	where
-		unfold_application  mod_index macro_ident opt_var {symb_kind=SK_Constructor {glob_module,glob_object},symb_name,symb_arity} args 
-										ums=:{ums_cons_defs, ums_modules,ums_error}
-				# (cons_def, cons_index, ums_cons_defs, ums_modules) = get_cons_def mod_index glob_module glob_object ums_cons_defs ums_modules
-				| cons_def.cons_type.st_arity == symb_arity
-					# (patterns, ums) = mapSt (unfold_pattern_macro mod_index macro_ident No) app_args { ums & ums_cons_defs = ums_cons_defs, ums_modules = ums_modules }
-					  cons_symbol = { glob_object = MakeDefinedSymbol symb_name cons_index symb_arity, glob_module = glob_module }	
-					= (AP_Algebraic cons_symbol cons_def.cons_type_index patterns opt_var, ums)	
-					= (AP_Empty cons_def.cons_symb, { ums & ums_cons_defs = ums_cons_defs, ums_modules = ums_modules,
-							ums_error = checkError cons_def.cons_symb " missing argument(s)" ums_error })
-
-		get_cons_def mod_index cons_mod cons_index cons_defs modules
-			| mod_index == cons_mod
-				# (cons_def, cons_defs) = cons_defs![cons_index]
-				= (cons_def, cons_index, cons_defs, modules)
-				# ({dcl_common,dcl_conversions}, modules) = modules![cons_mod]
-				  cons_def = dcl_common.com_cons_defs.[cons_index]
-				= (cons_def, convertIndex cons_index (toInt STE_Constructor) dcl_conversions, cons_defs, modules)
-		get_cons_def mod_index cons_mod cons_index cons_defs modules
-			# ({dcl_common,dcl_conversions}, modules) = modules![cons_mod]
-			  cons_def = dcl_common.com_cons_defs.[cons_index]
-			= (cons_def, convertIndex cons_index (toInt STE_Constructor) dcl_conversions, cons_defs, modules)
-
-	unfold_pattern_macro mod_index macro_ident opt_var (BasicExpr bv bt) ums
-		= (AP_Basic bv opt_var, ums)
-	unfold_pattern_macro mod_index macro_ident opt_var expr ums=:{ums_error}
-		= (AP_Empty macro_ident, { ums & ums_error = checkError macro_ident " illegal rhs for a pattern macro" ums_error })
-	
-checkPatternVariable :: !Level !SymbolTableEntry !Ident !VarInfoPtr !*CheckState -> !*CheckState
-checkPatternVariable def_level entry=:{ste_def_level,ste_kind} ident=:{id_info} var_info cs=:{cs_symbol_table,cs_error}
-	| ste_kind == STE_Empty || def_level > ste_def_level
-		# entry = {ste_kind = STE_Variable var_info, ste_index = NoIndex, ste_def_level = def_level, ste_previous = entry }
-		= { cs & cs_symbol_table = cs_symbol_table <:= (id_info,entry)}
-		= { cs & cs_error = checkError ident "(pattern variable) already defined" cs_error }
-
-checkPatternConstructor :: !Index !Bool !SymbolTableEntry !Ident !(Optional (Bind Ident VarInfoPtr)) !*PatternState !*ExpressionInfo !*CheckState
-	-> (!AuxiliaryPattern, !*PatternState, !*ExpressionInfo, !*CheckState);
-checkPatternConstructor _ _ {ste_kind = STE_Empty} ident _  ps e_info cs=:{cs_error}
-	= (AP_Empty ident, ps, e_info, { cs & cs_error = checkError ident " not defined" cs_error })
-checkPatternConstructor mod_index is_expr_list {ste_kind = STE_FunctionOrMacro _,ste_index} ident opt_var  ps=:{ps_fun_defs} e_info cs=:{cs_error,cs_x}
-	# ({fun_symb,fun_arity,fun_kind,fun_priority},ps_fun_defs) = ps_fun_defs![ste_index]
-	  ps = { ps & ps_fun_defs = ps_fun_defs }
-	| case fun_kind of FK_DefMacro->True ; FK_ImpMacro->True; _ -> False
-		| is_expr_list
-			# macro_symbol = { glob_object = MakeDefinedSymbol fun_symb ste_index fun_arity, glob_module = cs_x.x_main_dcl_module_n }
-	 		= (AP_Constant APK_Macro macro_symbol fun_priority, ps, e_info, cs)
-		| fun_arity == 0
-			# (pattern, ps, ef_modules, ef_cons_defs, cs_error)
-					= unfoldPatternMacro mod_index ste_index [] opt_var ps e_info.ef_modules e_info.ef_cons_defs cs_error
-			= (pattern, ps, { e_info & ef_modules = ef_modules, ef_cons_defs = ef_cons_defs }, { cs & cs_error = cs_error })
-			= (AP_Empty ident, ps, e_info, { cs & cs_error = checkError ident " not defined" cs_error })
-		= (AP_Empty ident, ps, e_info, { cs & cs_error = checkError fun_symb " not allowed in a pattern" cs_error })
-checkPatternConstructor mod_index is_expr_list {ste_index, ste_kind} cons_symb opt_var ps
-		e_info=:{ef_cons_defs,ef_modules} cs=:{cs_error}
-	# (cons_index, cons_module, cons_arity, cons_priority, cons_type_index, ef_cons_defs, ef_modules, cs_error)
-			= determine_pattern_symbol mod_index ste_index ste_kind cons_symb.id_name ef_cons_defs ef_modules cs_error
-	  e_info = { e_info & ef_cons_defs = ef_cons_defs, ef_modules = ef_modules }
-	  cons_symbol = { glob_object = MakeDefinedSymbol cons_symb cons_index cons_arity, glob_module = cons_module }
-   	| is_expr_list
-		= (AP_Constant (APK_Constructor cons_type_index) cons_symbol cons_priority, ps, e_info, { cs & cs_error = cs_error })
-	| cons_arity == 0
-		= (AP_Algebraic cons_symbol cons_type_index [] opt_var, ps, e_info, { cs & cs_error = cs_error })
-		= (AP_Algebraic cons_symbol cons_type_index [] opt_var, ps, e_info, { cs & cs_error = checkError cons_symb " constructor arguments are missing" cs_error })
-where
-	determine_pattern_symbol mod_index id_index STE_Constructor id_name cons_defs modules error
-		# ({cons_type={st_arity},cons_priority, cons_type_index}, cons_defs) = cons_defs![id_index]
-		= (id_index, mod_index, st_arity, cons_priority, cons_type_index, cons_defs, modules, error)
-	determine_pattern_symbol mod_index id_index (STE_Imported STE_Constructor import_mod_index) id_name cons_defs modules error
-		# ({dcl_common,dcl_conversions},modules) = modules![import_mod_index]
-		  {cons_type={st_arity},cons_priority, cons_type_index} = dcl_common.com_cons_defs.[id_index]
-		  id_index = convertIndex id_index (toInt STE_Constructor) dcl_conversions
-		= (id_index, import_mod_index, st_arity, cons_priority, cons_type_index, cons_defs, modules, error)
-	determine_pattern_symbol mod_index id_index id_kind id_name cons_defs modules error
-		= (id_index, NoIndex, 0, NoPrio, NoIndex, cons_defs, modules, checkError id_name " constructor expected" error)
-
-checkIdentPattern :: !Bool !Ident !(Optional (Bind Ident VarInfoPtr)) !PatternInput !(![Ident], ![ArrayPattern]) !*PatternState !*ExpressionInfo !*CheckState
-	-> (!AuxiliaryPattern, !(![Ident], ![ArrayPattern]), !*PatternState, !*ExpressionInfo, !*CheckState)
-checkIdentPattern is_expr_list id=:{id_name,id_info} opt_var {pi_def_level, pi_mod_index} accus=:(var_env, array_patterns)
-					ps e_info cs=:{cs_symbol_table}
-	# (entry, cs_symbol_table) = readPtr id_info cs_symbol_table
-	| isLowerCaseName id_name
-		# (new_info_ptr, ps_var_heap) = newPtr VI_Empty ps.ps_var_heap
-		  cs = checkPatternVariable pi_def_level entry id new_info_ptr { cs & cs_symbol_table = cs_symbol_table }
-		= (AP_Variable id new_info_ptr opt_var, ([ id : var_env ], array_patterns), { ps & ps_var_heap = ps_var_heap}, e_info, cs)
-		# (pattern, ps, e_info, cs) = checkPatternConstructor pi_mod_index is_expr_list entry id opt_var ps e_info { cs & cs_symbol_table = cs_symbol_table }
-		= (pattern, accus, ps, e_info, cs)
-
-::	PatternState =
-	{	ps_var_heap :: !.VarHeap
-	,	ps_fun_defs :: !.{# FunDef}
-	}
-
-::	PatternInput =
-	{	pi_def_level		:: !Int
-	,	pi_mod_index		:: !Index
-	,	pi_is_node_pattern	:: !Bool
-	}
-	
-::	ArrayPattern =
-	{	ap_opt_var		:: !Optional (Bind Ident VarInfoPtr)
-	,	ap_array_var	:: !FreeVar
-	,	ap_selections	:: ![Bind FreeVar [ParsedExpr]]
-	}
-
-buildPattern mod_index (APK_Constructor type_index) cons_symb args opt_var ps e_info cs
-	= (AP_Algebraic cons_symb type_index args opt_var, ps, e_info, cs)
-buildPattern mod_index APK_Macro {glob_object} args opt_var ps e_info=:{ef_modules,ef_cons_defs} cs=:{cs_error}
-	# (pattern, ps, ef_modules, ef_cons_defs, cs_error)
-			= unfoldPatternMacro mod_index glob_object.ds_index args opt_var ps ef_modules ef_cons_defs cs_error
-	= (pattern, ps, { e_info & ef_modules = ef_modules, ef_cons_defs = ef_cons_defs }, { cs & cs_error = cs_error })
-
-checkPattern :: !ParsedExpr !(Optional (Bind Ident VarInfoPtr)) !PatternInput !(![Ident], ![ArrayPattern]) !*PatternState !*ExpressionInfo !*CheckState
-									-> (!AuxiliaryPattern, !(![Ident], ![ArrayPattern]), !*PatternState, !*ExpressionInfo, !*CheckState)
-checkPattern (PE_List [exp]) opt_var p_input accus ps e_info cs=:{cs_symbol_table}
-	= case exp of
-		PE_Ident ident
-			-> checkIdentPattern cIsNotInExpressionList ident opt_var p_input accus ps e_info cs
-		_
-			-> checkPattern exp opt_var p_input accus ps e_info cs
-
-checkPattern (PE_List [exp1, exp2 : exps]) opt_var p_input accus ps e_info cs
-	# (exp_pat, accus, ps, e_info, cs) = check_pattern exp1 p_input accus ps e_info cs
-	= check_patterns [exp_pat] exp2 exps opt_var p_input accus ps e_info cs
-	where
-		check_patterns left middle [] opt_var p_input=:{pi_mod_index} accus ps e_info cs
-			# (mid_pat, accus, ps, e_info, cs) = checkPattern middle No p_input accus ps e_info cs
-			  (pat, ps, e_info, cs) = combine_patterns pi_mod_index opt_var [mid_pat : left] [] 0 ps e_info cs
-			= (pat, accus, ps, e_info, cs)
-		check_patterns left middle [right:rest] opt_var p_input=:{pi_mod_index} accus ps e_info cs
-			# (mid_pat, accus, ps, e_info, cs) = check_pattern middle p_input accus ps e_info cs
-			= case mid_pat of
-				AP_Constant kind constant=:{glob_object={ds_arity,ds_ident}} prio
-					| ds_arity == 0
-						# (pattern, ps, e_info, cs) = buildPattern pi_mod_index kind constant [] No ps e_info cs
-						-> check_patterns [pattern: left] right rest opt_var p_input accus ps e_info cs
-					| is_infix_constructor prio
-						# (left_arg, ps, e_info, cs) = combine_patterns pi_mod_index No left [] 0 ps e_info cs
-						  (right_pat, accus, ps, e_info, cs) = check_pattern right p_input accus ps e_info cs
-						-> check_infix_pattern [] left_arg kind constant prio [right_pat] rest
-									opt_var p_input accus ps e_info cs
-						-> (AP_Empty ds_ident, accus, ps, e_info,
-								{ cs & cs_error = checkError ds_ident "arguments of constructor are missing" cs.cs_error })
-				_
-					-> check_patterns [mid_pat : left] right rest opt_var p_input accus ps e_info cs
-
-		check_pattern (PE_Ident id) p_input accus ps e_info cs
-			= checkIdentPattern cIsInExpressionList id No p_input accus ps e_info cs
-		check_pattern expr p_input accus ps e_info cs
-			= checkPattern expr No p_input accus ps e_info cs
-		
-	 	check_infix_pattern left_args left kind cons prio middle [] opt_var p_input=:{pi_mod_index} accus ps e_info cs
-			# (middle_pat, ps, e_info, cs) = combine_patterns pi_mod_index No middle [] 0 ps e_info cs
-			  (pattern, ps, e_info, cs) = buildPattern pi_mod_index kind cons [left,middle_pat] opt_var ps e_info cs
-			  (pattern, ps, e_info, cs) = build_final_pattern pi_mod_index left_args pattern ps e_info cs
-			= (pattern, accus, ps, e_info, cs)
-	 	check_infix_pattern left_args left kind cons prio middle [right] opt_var  p_input=:{pi_mod_index} accus ps e_info cs
-			# (right_pat, accus, ps, e_info, cs) = checkPattern right No p_input accus ps e_info cs
-			  (right_arg, ps, e_info, cs) = combine_patterns pi_mod_index No [right_pat : middle] [] 0 ps e_info cs
-			  (pattern, ps, e_info, cs) = buildPattern pi_mod_index kind cons [left,right_arg] opt_var ps e_info cs
-			  (pattern, ps, e_info, cs) = build_final_pattern pi_mod_index left_args pattern ps e_info cs
-			= (pattern, accus, ps, e_info, cs)
-	 	check_infix_pattern left_args left kind1 cons1 prio1 middle [inf_cons, arg : rest] opt_var p_input=:{pi_mod_index} accus ps e_info cs
-			# (inf_cons_pat, accus, ps, e_info, cs) = check_pattern inf_cons p_input accus ps e_info cs
-			= case inf_cons_pat of
-				AP_Constant kind2 cons2=:{glob_object={ds_ident,ds_arity}} prio2
-					| ds_arity == 0
-						# (middle_pat, ps, e_info, cs) = combine_patterns pi_mod_index No middle [] 0 ps e_info cs
-						  (pattern2, ps, e_info, cs) = buildPattern pi_mod_index kind2 cons2 [] No ps e_info cs
-						  (pattern1, ps, e_info, cs) = buildPattern pi_mod_index kind1 cons1 [left,middle_pat] No ps e_info cs
-						  (pattern1, ps, e_info, cs) = build_final_pattern pi_mod_index left_args pattern1 ps e_info cs
-						-> check_patterns [pattern2,pattern1] arg rest opt_var p_input accus ps e_info cs
-					| is_infix_constructor prio2
-						# optional_prio = determinePriority prio1 prio2
-						-> case optional_prio of
-							Yes priority
-								# (arg_pat, accus, ps, e_info, cs) = check_pattern arg p_input accus ps e_info cs
-								| priority
-									# (middle_pat, ps, e_info, cs) = combine_patterns pi_mod_index No middle [] 0 ps e_info cs
-								      (pattern, ps, e_info, cs) = buildPattern pi_mod_index kind1 cons1 [left,middle_pat] No ps e_info cs
-								      (left_args, pattern, ps, e_info, cs) = build_left_pattern pi_mod_index left_args prio2 pattern ps e_info cs
-									-> check_infix_pattern left_args pattern kind2 cons2 prio2 [arg_pat] rest opt_var p_input accus ps e_info cs 
-									# (middle_pat, ps, e_info, cs) = combine_patterns pi_mod_index No middle [] 0 ps e_info cs
-									-> check_infix_pattern [(kind1, cons1, prio1, left) : left_args]
-									  				middle_pat kind2 cons2 prio2 [arg_pat] rest No p_input accus ps e_info cs
-							No
-								-> (AP_Empty ds_ident, accus, ps, e_info, { cs & cs_error = checkError ds_ident "conflicting priorities" cs.cs_error })
-						-> (AP_Empty ds_ident, accus, ps, e_info, { cs & cs_error = checkError ds_ident "arguments of constructor are missing" cs.cs_error })
-				_
-					-> check_infix_pattern left_args left kind1 cons1 prio1 [inf_cons_pat : middle] [arg : rest] opt_var p_input accus ps e_info cs 
-
-		is_infix_constructor (Prio _ _) = True
-		is_infix_constructor _ = False
-
-		build_left_pattern mod_index [] _ result_pattern ps e_info cs
-			= ([], result_pattern, ps, e_info, cs)		
-		build_left_pattern mod_index la=:[(kind, cons, priol, left) : left_args] prior result_pattern ps e_info cs
-			# optional_prio = determinePriority priol prior
-			= case optional_prio of
-				Yes priority
-					| priority
-						# (result_pattern,  ps, e_info, cs) = buildPattern mod_index kind cons [left,result_pattern] No ps e_info cs
-						-> build_left_pattern mod_index left_args prior result_pattern ps e_info cs
-						-> (la, result_pattern,  ps, e_info, cs)
-				No
-					-> (la, result_pattern,  ps, e_info,{ cs & cs_error = checkError cons.glob_object.ds_ident "conflicting priorities" cs.cs_error })
-
-		build_final_pattern mod_index [] result_pattern ps e_info cs
-			= (result_pattern,  ps, e_info, cs)		
-		build_final_pattern mod_index [(kind, cons, priol, left) : left_appls] result_pattern ps e_info cs
-			# (result_pattern, ps, e_info, cs) = buildPattern mod_index kind cons [left,result_pattern] No ps e_info cs
-			= build_final_pattern mod_index left_appls result_pattern ps e_info cs
-
-		combine_patterns mod_index opt_var [first_expr] args nr_of_args ps e_info cs
-			= case first_expr of
-				AP_Constant kind constant=:{glob_object={ds_ident,ds_arity}} _
-					| ds_arity == nr_of_args
-						# (pattern, ps, e_info, cs) = buildPattern mod_index kind constant args opt_var ps e_info cs
-						-> (pattern, ps, e_info, cs)
-						-> (AP_Empty ds_ident, ps, e_info, { cs & cs_error = checkError ds_ident "used with wrong arity" cs.cs_error})
-				_
-					| nr_of_args == 0
-						-> (first_expr, ps, e_info, cs)
-						-> (first_expr, ps, e_info, { cs & cs_error = checkError "<pattern>" "(curried) application not allowed " cs.cs_error })
-		combine_patterns mod_index opt_var [rev_arg : rev_args] args arity ps e_info cs
-			= combine_patterns mod_index opt_var rev_args [rev_arg : args] (inc arity) ps e_info cs
-/*
-		combine_optional_variables (Yes var1) (Yes var2) error
-			= (Yes var1, checkError var2.bind_dst "pattern already bound" error)
-		combine_optional_variables No opt_var error
-			= (opt_var, error)
-		combine_optional_variables opt_var _ error
-			= (opt_var, error)
-*/
-
-checkPattern (PE_DynamicPattern pattern type) opt_var p_input accus ps e_info cs=:{cs_x}
-	# (dyn_pat, accus, ps, e_info, cs) = checkPattern pattern No p_input accus ps e_info cs
-	= (AP_Dynamic dyn_pat type opt_var, accus, ps, e_info, { cs & cs_x.x_needed_modules = cs_x.x_needed_modules bitor cNeedStdDynamics })
-
-checkPattern (PE_Basic basic_value) opt_var p_input accus ps e_info cs
-	= (AP_Basic basic_value opt_var, accus, ps, e_info, cs)
-
-checkPattern (PE_Tuple tuple_args) opt_var p_input accus ps e_info cs
-	# (patterns, arity, accus, ps, e_info, cs) = check_tuple_patterns tuple_args p_input accus ps e_info cs
-	  (tuple_symbol, cs) = getPredefinedGlobalSymbol (GetTupleConsIndex arity) PD_PredefinedModule STE_Constructor arity cs
-	# ({cons_type_index}, e_info) = e_info!ef_modules.[tuple_symbol.glob_module].dcl_common.com_cons_defs.[tuple_symbol.glob_object.ds_index]
-	= (AP_Algebraic tuple_symbol cons_type_index patterns opt_var, accus, ps, e_info, cs)
-where
-	check_tuple_patterns [] p_input accus ps e_info cs
-		= ([], 0, accus, ps, e_info, cs)
-	check_tuple_patterns [expr : exprs] p_input accus ps e_info cs
-		# (pattern, accus, ps, e_info, cs) = checkPattern expr No p_input accus ps e_info cs
-		  (patterns, length, accus, ps, e_info, cs) = check_tuple_patterns exprs p_input accus ps e_info cs
-		= ([pattern : patterns], inc length, accus, ps, e_info, cs)
-checkPattern (PE_Record record opt_type fields) opt_var p_input=:{pi_mod_index, pi_is_node_pattern} accus=:(var_env, array_patterns) ps e_info cs
-	# (opt_record_and_fields, e_info, cs) = checkFields pi_mod_index fields opt_type e_info cs
-	= case opt_record_and_fields of
-		Yes (record_symbol, type_index, new_fields)
-			# (patterns, (var_env, array_patterns, ps, e_info, cs)) = mapSt (check_field_pattern p_input) new_fields (var_env, array_patterns, ps, e_info, cs)
-			  (patterns, ps_var_heap) = bind_opt_record_variable opt_var pi_is_node_pattern patterns new_fields ps.ps_var_heap
-			-> (AP_Algebraic record_symbol type_index patterns opt_var, (var_env, array_patterns), { ps & ps_var_heap = ps_var_heap }, e_info, cs)
-		No
-			-> (AP_Empty (hd fields).bind_dst, accus, ps, e_info, cs)
-where
-
-	check_field_pattern p_input=:{pi_def_level} {bind_src = PE_Empty, bind_dst = {glob_object={fs_var}}} 
-						(var_env, array_patterns, ps, e_info, cs)
-		# (entry, cs_symbol_table) = readPtr fs_var.id_info cs.cs_symbol_table
-		# (new_info_ptr, ps_var_heap) = newPtr VI_Empty ps.ps_var_heap
-		  cs = checkPatternVariable pi_def_level entry fs_var new_info_ptr { cs & cs_symbol_table = cs_symbol_table }
-		= (AP_Variable fs_var new_info_ptr No, ([ fs_var : var_env ], array_patterns, { ps & ps_var_heap = ps_var_heap }, e_info, cs))
-	check_field_pattern p_input {bind_src = PE_WildCard, bind_dst={glob_object={fs_var}}} (var_env, array_patterns, ps, e_info, cs)
-		# (new_info_ptr, ps_var_heap) = newPtr VI_Empty ps.ps_var_heap
-		= (AP_WildCard (Yes { bind_src = fs_var, bind_dst = new_info_ptr}), (var_env, array_patterns, { ps & ps_var_heap = ps_var_heap }, e_info, cs))
-	check_field_pattern p_input {bind_src,bind_dst} (var_env, array_patterns, ps, e_info, cs)
-		# (pattern, (var_env, array_patterns), ps, e_info, cs) = checkPattern bind_src No p_input (var_env, array_patterns) ps e_info cs
-		= (pattern, (var_env, array_patterns, ps, e_info, cs))
-
-
-	add_bound_variable (AP_Algebraic symbol index patterns No) {bind_dst = {glob_object={fs_var}}} ps_var_heap
-		# (new_info_ptr, ps_var_heap) = newPtr VI_Empty ps_var_heap
-		= (AP_Algebraic symbol index patterns (Yes { bind_src = fs_var, bind_dst = new_info_ptr}), ps_var_heap)
-	add_bound_variable (AP_Basic bas_val No) {bind_dst = {glob_object={fs_var}}} ps_var_heap
-		# (new_info_ptr, ps_var_heap) = newPtr VI_Empty ps_var_heap
-		= (AP_Basic bas_val (Yes { bind_src = fs_var, bind_dst = new_info_ptr}), ps_var_heap)
-	add_bound_variable (AP_Dynamic dynamic_pattern dynamic_type No) {bind_dst = {glob_object={fs_var}}} ps_var_heap
-		# (new_info_ptr, ps_var_heap) = newPtr VI_Empty ps_var_heap
-		= (AP_Dynamic dynamic_pattern dynamic_type (Yes { bind_src = fs_var, bind_dst = new_info_ptr}), ps_var_heap)
-	add_bound_variable pattern _ ps_var_heap
-		= (pattern, ps_var_heap)
-
-	add_bound_variables [] _ var_heap
-		= ([] , var_heap)
-	add_bound_variables [ap : aps] [field : fields] var_heap
-		# (ap, var_heap) = add_bound_variable ap field var_heap
-		  (aps, var_heap) = add_bound_variables aps fields var_heap
-		= ([ap : aps], var_heap)
-
-	bind_opt_record_variable (Yes {bind_dst}) False patterns fields var_heap
-		# (patterns, var_heap) = add_bound_variables patterns fields var_heap
-		= (patterns, var_heap <:= (bind_dst, VI_Record patterns))
-	bind_opt_record_variable no is_node_pattern patterns _ var_heap
-		= (patterns, var_heap)
-
-checkPattern (PE_Bound bind) opt_var p_input accus ps e_info cs
-	= checkBoundPattern bind opt_var p_input accus ps e_info cs
-checkPattern (PE_Ident id) opt_var p_input accus ps e_info cs
-	= checkIdentPattern cIsNotInExpressionList id opt_var p_input accus ps e_info cs
-checkPattern PE_WildCard opt_var p_input accus ps e_info cs
-	= (AP_WildCard No, accus, ps, e_info, cs)
-checkPattern (PE_ArrayPattern selections) opt_var p_input (var_env, array_patterns) ps e_info cs
-	# (var_env, ap_selections, ps_var_heap, cs)
-			= foldSt (check_array_selection p_input.pi_def_level) selections (var_env, [], ps.ps_var_heap, cs)
-	  array_var_ident = case opt_var of 
-	  						Yes {bind_src}
-	  							-> bind_src
-	  						No
-	  							-> { id_name = "_a", id_info = nilPtr }
-	  (array_var, ps_var_heap) = allocate_free_var array_var_ident ps_var_heap
-	= (AP_Variable array_var_ident array_var.fv_info_ptr No, 
-		(var_env, [{ ap_opt_var = opt_var, ap_array_var = array_var, ap_selections = ap_selections } :array_patterns]),
-		{ ps & ps_var_heap = ps_var_heap }, e_info, cs)
-  where
-	check_array_selection def_level bind=:{bind_dst} states
-		= check_rhs def_level bind (foldSt check_index_expr bind_dst states)
-		
-	check_index_expr (PE_Ident {id_name}) states
-		| isLowerCaseName id_name
-			= states
-		// further with next alternative
-	check_index_expr (PE_Basic (BVI _)) states
-			= states
-	check_index_expr _ (var_env, ap_selections, var_heap, cs)
-		= (var_env, ap_selections, var_heap, { cs & cs_error = checkError "" "variable or integer constant expected as index expression" cs.cs_error })
-
-	check_rhs def_level {bind_src=PE_Ident ident, bind_dst} (var_env, ap_selections, var_heap, cs)
-		| isLowerCaseName ident.id_name
-			# (entry,cs_symbol_table) = readPtr ident.id_info cs.cs_symbol_table
-			# (rhs_var, var_heap) = allocate_free_var ident var_heap
-			  cs = checkPatternVariable def_level entry ident rhs_var.fv_info_ptr { cs & cs_symbol_table = cs_symbol_table }
-			= ([ident : var_env], [ { bind_src = rhs_var, bind_dst = bind_dst } : ap_selections], var_heap, cs)
-		// further with next alternative
-	check_rhs _ _ (var_env, ap_selections, var_heap, cs)
-		= (var_env, ap_selections, var_heap, 
-			{ cs & cs_error = checkError "" "variable expected on right hand side of array pattern" cs.cs_error })
-checkPattern expr opt_var p_input accus ps e_info cs
-	= abort "checkPattern: do not know how to handle pattern" ---> expr
-
-checkBoundPattern {bind_src,bind_dst} opt_var p_input (var_env, array_patterns) ps e_info cs=:{cs_symbol_table}
-	| isLowerCaseName bind_dst.id_name
-		# (entry, cs_symbol_table) = readPtr bind_dst.id_info cs_symbol_table
-		# (new_info_ptr, ps_var_heap) = newPtr VI_Empty ps.ps_var_heap
-		  cs = checkPatternVariable p_input.pi_def_level entry bind_dst new_info_ptr { cs & cs_symbol_table = cs_symbol_table }
-		  ps = { ps & ps_var_heap = ps_var_heap }
-		  new_var_env = [ bind_dst : var_env ]
-		= case opt_var of
-			Yes bind
-				-> checkPattern bind_src (Yes { bind_src = bind_dst, bind_dst = new_info_ptr }) p_input (new_var_env, array_patterns) ps
-					 	e_info { cs & cs_error = checkError bind.bind_src "pattern may be bound once only" cs.cs_error }
-			No
-				-> checkPattern bind_src (Yes { bind_src = bind_dst, bind_dst = new_info_ptr }) p_input (new_var_env, array_patterns) ps e_info cs
-	= checkPattern bind_src opt_var p_input (var_env, array_patterns) ps e_info { cs & cs_error = checkError bind_dst "variable expected" cs.cs_error }
-
-newFreeVariable :: !FreeVar ![FreeVar] ->(!Bool, ![FreeVar])
-newFreeVariable new_var vars=:[free_var=:{fv_def_level,fv_info_ptr}: free_vars]
-	| new_var.fv_def_level > fv_def_level
-		= (True, [new_var : vars])
-	| new_var.fv_def_level == fv_def_level
-		| new_var.fv_info_ptr == fv_info_ptr
-			= (False, vars)
-			#! (free_var_added, free_vars) = newFreeVariable new_var free_vars
-			= (free_var_added, [free_var : free_vars])
-		#! (free_var_added, free_vars) = newFreeVariable new_var free_vars
-		= (free_var_added, [free_var : free_vars])
-newFreeVariable new_var []
-	= (True, [new_var])
-
-
-buildTypeCase type_case_dynamic type_case_patterns type_case_default type_case_info_ptr :==
-	Case {	case_expr = type_case_dynamic, case_guards = DynamicPatterns type_case_patterns, case_default = type_case_default, 
-			case_info_ptr = type_case_info_ptr, case_ident = No, case_default_pos = NoPos }
 
 
 consOptional (Yes thing) things
@@ -1047,1330 +462,7 @@ consOptional (Yes thing) things
 consOptional No things
 	= things
 
-buildApplication :: !SymbIdent !Int !Int !Bool ![Expression] !*ExpressionState !*ErrorAdmin -> (!Expression,!*ExpressionState,!*ErrorAdmin)
-buildApplication symbol form_arity act_arity is_fun args e_state=:{es_expr_heap} error
-	| is_fun
-		# (new_info_ptr, es_expr_heap) = newPtr EI_Empty es_expr_heap
-		| form_arity < act_arity
-			# app = { app_symb = { symbol & symb_arity = form_arity }, app_args = take form_arity args, app_info_ptr = new_info_ptr }
-			= (App app @ drop form_arity args, { e_state & es_expr_heap = es_expr_heap }, error)
-			# app = { app_symb = { symbol & symb_arity = act_arity }, app_args = take form_arity args, app_info_ptr = new_info_ptr }
-			= (App app, { e_state & es_expr_heap = es_expr_heap }, error)
-		# app = App { app_symb = { symbol & symb_arity = act_arity }, app_args = args, app_info_ptr = nilPtr }
-		| form_arity < act_arity
-			= (app, e_state, checkError symbol.symb_name " used with too many arguments" error)
-			= (app, e_state, error)
-
-checkIdentExpression :: !Bool ![FreeVar] !Ident !ExpressionInput !*ExpressionState !u:ExpressionInfo !*CheckState
-	-> (!Expression, ![FreeVar], !*ExpressionState, !u:ExpressionInfo, !*CheckState)
-checkIdentExpression is_expr_list free_vars id=:{id_info} e_input e_state e_info cs=:{cs_symbol_table}
-	# (entry, cs_symbol_table) = readPtr id_info cs_symbol_table
-	= check_id_expression entry is_expr_list free_vars id e_input e_state e_info { cs & cs_symbol_table = cs_symbol_table }
-where
-	check_id_expression :: !SymbolTableEntry !Bool ![FreeVar] !Ident !ExpressionInput !*ExpressionState !u:ExpressionInfo !*CheckState
-		-> (!Expression, ![FreeVar], !*ExpressionState, !u:ExpressionInfo, !*CheckState)
-
-	check_id_expression {ste_kind = STE_Empty} is_expr_list free_vars id e_input e_state e_info cs=:{cs_error,cs_predef_symbols,cs_x}
-		# ({pds_ident=from_ident}) = cs_predef_symbols.[PD_From]
-		  ({pds_ident=from_then_ident}) = cs_predef_symbols.[PD_FromThen]
-		  ({pds_ident=from_to_ident}) = cs_predef_symbols.[PD_FromTo]
-		  ({pds_ident=from_then_to_ident}) = cs_predef_symbols.[PD_FromThenTo]
-		| id==from_ident || id==from_then_ident || id==from_to_ident || id==from_then_to_ident
-			= (EE, free_vars, e_state, e_info, { cs & cs_x.x_needed_modules = cs_x.x_needed_modules bitor cNeedStdEnum})
-				// instead of giving an error message remember that StdEnum should have been imported.
-				// Error will be given in function check_needed_modules_are_imported
-		# ({pds_ident=createArray_ident}) = cs_predef_symbols.[PD__CreateArrayFun]
-		  ({pds_ident=uselect_ident}) = cs_predef_symbols.[PD_UnqArraySelectFun]
-		  ({pds_ident=update_ident}) = cs_predef_symbols.[PD_ArrayUpdateFun]
-		  ({pds_ident=usize_ident}) = cs_predef_symbols.[PD_UnqArraySizeFun]
-		| id==createArray_ident || id==uselect_ident || id==update_ident || id==usize_ident
-			= (EE, free_vars, e_state, e_info, { cs & cs_x.x_needed_modules = cs_x.x_needed_modules bitor cNeedStdArray})
-				// instead of giving an error message remember that StdArray should have been be imported.
-				//  Error will be given in function check_needed_modules_are_imported
-		= (EE, free_vars, e_state, e_info, { cs & cs_error = checkError id "undefined" cs_error })
-	check_id_expression {ste_kind = STE_Variable info_ptr,ste_def_level} is_expr_list free_vars id e_input=:{ei_fun_level} e_state=:{es_expr_heap} e_info cs
-		| ste_def_level < ei_fun_level
-			# free_var = { fv_def_level = ste_def_level, fv_name = id, fv_info_ptr = info_ptr, fv_count = 0 }
-			  (free_var_added, free_vars) = newFreeVariable free_var free_vars
-			= (FreeVar free_var, free_vars, e_state, e_info, cs)
-			#! (var_expr_ptr, es_expr_heap) = newPtr EI_Empty es_expr_heap
-			= (Var {var_name = id, var_info_ptr = info_ptr, var_expr_ptr = var_expr_ptr}, free_vars,
-					{e_state & es_expr_heap = es_expr_heap}, e_info, cs)
-	check_id_expression entry is_expr_list free_vars id=:{id_info} e_input e_state e_info cs
-		# (symb_kind, arity, priority, is_a_function, e_state, e_info, cs) = determine_info_of_symbol entry id_info e_input e_state e_info cs
-		  symbol = { symb_name = id, symb_kind = symb_kind, symb_arity = 0 }
-  		| is_expr_list
-			= (Constant symbol arity priority is_a_function, free_vars, e_state, e_info, cs)
-			# (app_expr, e_state, cs_error) = buildApplication symbol arity 0 is_a_function [] e_state cs.cs_error
-			= (app_expr, free_vars, e_state, e_info, { cs & cs_error = cs_error })
-
-	determine_info_of_symbol :: !SymbolTableEntry !SymbolPtr !ExpressionInput !*ExpressionState !u:ExpressionInfo !*CheckState
-		-> (!SymbKind, !Int, !Priority, !Bool, !*ExpressionState, !u:ExpressionInfo,!*CheckState)
-	determine_info_of_symbol entry=:{ste_kind=STE_FunctionOrMacro calls,ste_index,ste_def_level} symb_info
-				e_input=:{ei_fun_index, ei_mod_index} e_state=:{es_fun_defs,es_calls} e_info=:{ef_is_macro_fun} cs=:{cs_symbol_table,cs_x}
-		# ({fun_symb,fun_arity,fun_kind,fun_priority}, es_fun_defs) = es_fun_defs![ste_index]
-		# index = { glob_object = ste_index, glob_module = cs_x.x_main_dcl_module_n }
-		| is_called_before ei_fun_index calls
-			| case fun_kind of FK_DefMacro->True ; FK_ImpMacro->True; _ -> False
-				= (SK_Macro index, fun_arity, fun_priority, cIsAFunction, { e_state & es_fun_defs = es_fun_defs }, e_info, cs)
-				# symbol_kind = if ef_is_macro_fun (SK_LocalMacroFunction ste_index) (SK_Function index)
-				= (symbol_kind, fun_arity, fun_priority, cIsAFunction, { e_state & es_fun_defs = es_fun_defs }, e_info, cs)
-			# cs = { cs & cs_symbol_table = cs_symbol_table <:= (symb_info, { entry & ste_kind = STE_FunctionOrMacro [ ei_fun_index : calls ]})}
-			  e_state = { e_state & es_fun_defs = es_fun_defs, es_calls = [{ fc_index = ste_index, fc_level = ste_def_level} : es_calls ]}
-			# symbol_kind = case fun_kind of
-				FK_DefMacro
-					-> SK_Macro index;
-				FK_ImpMacro
-					-> SK_Macro index;
-				_
-					| ef_is_macro_fun
-						-> SK_LocalMacroFunction ste_index
-						-> SK_Function index
-			= (symbol_kind, fun_arity, fun_priority, cIsAFunction, e_state, e_info, cs)
-	where
-		is_called_before caller_index []
-			= False
-		is_called_before caller_index [called_index : calls]
-			= caller_index == called_index || is_called_before caller_index calls
-
-	determine_info_of_symbol entry=:{ste_kind=STE_Imported kind mod_index,ste_index} symb_index e_input e_state e_info=:{ef_modules} cs
-		# (mod_def, ef_modules) = ef_modules![mod_index]
-		# (kind, arity, priotity, is_fun) = ste_kind_to_symbol_kind kind ste_index mod_index mod_def
-		= (kind, arity, priotity, is_fun, e_state, { e_info & ef_modules = ef_modules }, cs)
-	where
-		ste_kind_to_symbol_kind :: !STE_Kind !Index !Index !DclModule -> (!SymbKind, !Int, !Priority, !Bool);
-		ste_kind_to_symbol_kind STE_DclFunction def_index mod_index {dcl_functions,dcl_conversions}
-			# {ft_type={st_arity},ft_priority} = dcl_functions.[def_index]
-			# def_index = convertIndex def_index (toInt STE_DclFunction) dcl_conversions
-			= (SK_Function { glob_object = def_index, glob_module = mod_index }, st_arity, ft_priority, cIsAFunction)
-		ste_kind_to_symbol_kind STE_Member def_index mod_index {dcl_common={com_member_defs},dcl_conversions}
-			# {me_type={st_arity},me_priority} = com_member_defs.[def_index]
-			# def_index = convertIndex def_index (toInt STE_Member) dcl_conversions
-			= (SK_OverloadedFunction { glob_object = def_index, glob_module = mod_index }, st_arity, me_priority, cIsAFunction)
-		ste_kind_to_symbol_kind STE_Constructor def_index mod_index {dcl_common={com_cons_defs},dcl_conversions}
-			# {cons_type={st_arity},cons_priority} = com_cons_defs.[def_index]
-			# def_index = convertIndex def_index (toInt STE_Constructor) dcl_conversions
-			= (SK_Constructor { glob_object = def_index, glob_module = mod_index }, st_arity, cons_priority, cIsNotAFunction)
-
-	determine_info_of_symbol {ste_kind=STE_Member, ste_index} _ e_input=:{ei_mod_index} e_state e_info=:{ef_member_defs} cs
-		# ({me_type={st_arity},me_priority}, ef_member_defs) = ef_member_defs![ste_index]
-		= (SK_OverloadedFunction { glob_object = ste_index, glob_module = ei_mod_index}, st_arity, me_priority, cIsAFunction,
-				e_state, { e_info & ef_member_defs = ef_member_defs }, cs)
-	determine_info_of_symbol {ste_kind=STE_Constructor, ste_index} _ e_input=:{ei_mod_index} e_state e_info=:{ef_cons_defs} cs
-		# ({cons_type={st_arity},cons_priority}, ef_cons_defs) = ef_cons_defs![ste_index]
-		= (SK_Constructor { glob_object = ste_index, glob_module =  ei_mod_index}, st_arity, cons_priority, cIsNotAFunction,
-				e_state, { e_info & ef_cons_defs = ef_cons_defs }, cs)
-	determine_info_of_symbol {ste_kind=STE_DclFunction, ste_index} _ e_input=:{ei_mod_index} e_state e_info=:{ef_modules} cs
-		# (mod_def, ef_modules) = ef_modules![ei_mod_index]
-		# {ft_type={st_arity},ft_priority} = mod_def.dcl_functions.[ste_index]
-		  def_index = convertIndex ste_index (toInt STE_DclFunction) mod_def.dcl_conversions
-		= (SK_Function { glob_object = def_index, glob_module =  ei_mod_index}, st_arity, ft_priority, cIsAFunction,
-				e_state, { e_info & ef_modules = ef_modules }, cs)
-
-::	RecordKind = RK_Constructor | RK_Update | RK_UpdateToConstructor ![AuxiliaryPattern]
-
-cEndWithUpdate :== True
-cEndWithSelection :== False
-
-checkExpression :: ![FreeVar] !ParsedExpr !ExpressionInput !*ExpressionState !*ExpressionInfo !*CheckState
-	-> *(!Expression, ![FreeVar], !*ExpressionState, !*ExpressionInfo, !*CheckState);
-checkExpression free_vars (PE_List exprs) e_input e_state e_info cs	
-	# (exprs, free_vars, e_state, e_info, cs) = check_expressions free_vars exprs e_input e_state e_info cs
-	  (expr, e_state, cs_error) = build_expression exprs e_state cs.cs_error
-	= (expr, free_vars, e_state, e_info, { cs & cs_error = cs_error })
 
-where
-	check_expressions free_vars [expr : exprs] e_input e_state e_info cs
-		# (exprs, free_vars, e_state, e_info, cs) = check_expressions free_vars exprs e_input e_state e_info cs
-		= case expr of
-			PE_Ident id
-				# (expr, free_vars, e_state, e_info, cs) = checkIdentExpression cIsInExpressionList free_vars id e_input e_state e_info cs
- 				-> ([expr : exprs], free_vars, e_state, e_info, cs)
- 			_
-				# (expr, free_vars, e_state, e_info, cs) = checkExpression free_vars expr e_input e_state e_info cs
- 				-> ([expr : exprs], free_vars, e_state, e_info, cs)
- 	check_expressions free_vars [] e_input e_state e_info cs
-		= ([], free_vars, e_state, e_info, cs)
-
-	first_argument_of_infix_operator_missing
-		= "first argument of infix operator missing"
-
-	build_expression [Constant symb _ (Prio _ _) _ , _: _] e_state cs_error
-		= (EE, e_state, checkError symb.symb_name first_argument_of_infix_operator_missing cs_error)
-	build_expression [Constant symb arity _ is_fun] e_state cs_error
-		= buildApplication symb arity 0 is_fun [] e_state cs_error
-	build_expression [expr] e_state cs_error
-		= (expr, e_state, cs_error)
-	build_expression [expr : exprs] e_state cs_error
-		# (opt_opr, left, e_state, cs_error) = split_at_operator [expr] exprs e_state cs_error
-		  (left_expr, e_state, cs_error) = combine_expressions left [] 0 e_state cs_error
-		= case opt_opr of
-			Yes (symb, prio, is_fun, right)
-				-> case right of
-					[Constant symb _ (Prio _ _) _:_]
-						-> (EE, e_state, checkError symb.symb_name first_argument_of_infix_operator_missing cs_error)
-					_
-						-> build_operator_expression [] left_expr (symb, prio, is_fun) right e_state cs_error
-			No
-				-> (left_expr, e_state, cs_error)
-	where
-		split_at_operator left [Constant symb arity NoPrio is_fun : exprs] e_state cs_error
-			# (appl_exp, e_state, cs_error) = buildApplication symb arity 0 is_fun [] e_state cs_error
-			= split_at_operator [appl_exp : left] exprs e_state cs_error
-		split_at_operator left [Constant symb arity (Prio _ _) is_fun] e_state cs_error
-			= (No, left, e_state, checkError symb.symb_name "second argument of infix operator missing" cs_error)
-		split_at_operator left [Constant symb arity prio is_fun] e_state cs_error
-			# (appl_exp, e_state, cs_error) = buildApplication symb arity 0 is_fun [] e_state cs_error
-			= (No, [appl_exp : left], e_state, cs_error)
-		split_at_operator left [expr=:(Constant symb _ prio is_fun) : exprs] e_state cs_error
-			= (Yes (symb, prio, is_fun, exprs), left, e_state, cs_error)
-		split_at_operator left [expr : exprs] e_state cs_error
-			= split_at_operator [expr : left] exprs e_state cs_error
-		split_at_operator exp [] e_state cs_error
-			= (No, exp, e_state, cs_error)
-
-		combine_expressions [first_expr] args arity e_state cs_error
-			= case first_expr of
-				Constant symb form_arity _ is_fun
-					# (app_exp, e_state, cs_error) = buildApplication symb form_arity arity is_fun args e_state cs_error
-					-> (app_exp, e_state, cs_error)
-				_
-					| arity == 0
-						-> (first_expr, e_state, cs_error)
-						-> (first_expr @ args, e_state, cs_error)
-		combine_expressions [rev_arg : rev_args] args arity e_state cs_error
-			= combine_expressions rev_args [rev_arg : args] (inc arity) e_state cs_error
-		
-
- 		build_operator_expression left_appls left1 (symb1, prio1, is_fun1) [re : res] e_state cs_error
-			# (opt_opr, left2, e_state, cs_error) = split_at_operator [re] res e_state cs_error
-			= case opt_opr of
-				Yes (symb2, prio2, is_fun2, right)
-					# optional_prio = determinePriority prio1 prio2
-					-> case optional_prio of
-						Yes priority
-							| priority
-						  		# (middle_exp, e_state, cs_error) = combine_expressions left2 [] 0 e_state cs_error
-								  (new_left, e_state, cs_error) = buildApplication symb1 2 2 is_fun1 [left1,middle_exp] e_state cs_error
-								  (left_appls, new_left, e_state, cs_error) = build_left_operand left_appls prio2 new_left e_state cs_error
-								-> build_operator_expression left_appls new_left (symb2, prio2, is_fun2) right e_state cs_error
-						  		# (middle_exp, e_state, cs_error) = combine_expressions left2 [] 0 e_state cs_error
-								-> build_operator_expression [(symb1, prio1, is_fun1, left1) : left_appls]
-										middle_exp (symb2, prio2, is_fun2) right e_state cs_error
-						No
-							-> (EE, e_state, checkError symb1.symb_name "conflicting priorities" cs_error)
-				No
-					# (right, e_state, cs_error) = combine_expressions left2 [] 0 e_state cs_error
-					  (result_expr, e_state, cs_error) = buildApplication symb1 2 2 is_fun1 [left1,right] e_state cs_error
-					-> build_final_expression left_appls result_expr e_state cs_error
-
-		build_left_operand [] _ result_expr e_state cs_error
-			= ([], result_expr, e_state, cs_error)		
-		build_left_operand la=:[(symb, priol, is_fun, left) : left_appls] prior result_expr e_state cs_error
-			# optional_prio = determinePriority priol prior
-			= case optional_prio of
-				Yes priority
-					| priority
-						# (result_expr, e_state, cs_error) = buildApplication symb 2 2 is_fun [left,result_expr] e_state cs_error
-						-> build_left_operand left_appls prior result_expr e_state cs_error
-						-> (la, result_expr, e_state, cs_error)
-				No
-					-> (la, EE, e_state, checkError symb.symb_name "conflicting priorities" cs_error)
-		
-		build_final_expression [] result_expr e_state cs_error
-			= (result_expr, e_state, cs_error)		
-		build_final_expression [(symb, _, is_fun, left) : left_appls] result_expr e_state cs_error
-			# (result_expr, e_state, cs_error) = buildApplication symb 2 2 is_fun [left,result_expr] e_state cs_error
-			= build_final_expression left_appls result_expr e_state cs_error
-					
-checkExpression free_vars (PE_Let strict let_locals expr) e_input=:{ei_expr_level,ei_mod_index} e_state e_info cs
-	# ei_expr_level = inc ei_expr_level
-	  (loc_defs, (var_env, array_patterns), e_state, e_info, cs)
-	  		= checkLhssOfLocalDefs ei_expr_level ei_mod_index let_locals e_state e_info cs
-	  e_input = { e_input & ei_expr_level = ei_expr_level }
-	  (let_expr, free_vars, e_state, e_info, cs) = checkExpression free_vars expr e_input e_state e_info cs
-	  (expr, free_vars, e_state=:{es_dynamics,es_expr_heap,es_var_heap}, e_info, cs)
-			= addArraySelections array_patterns let_expr free_vars e_input e_state e_info cs
-	  (expr, free_vars, e_state, e_info, cs) = checkRhssAndTransformLocalDefs free_vars loc_defs expr e_input e_state e_info cs
-	  (es_fun_defs, e_info, heaps, cs)
-			= checkLocalFunctions ei_mod_index ei_expr_level let_locals e_state.es_fun_defs e_info
-	  			{ hp_var_heap = e_state.es_var_heap, hp_expression_heap = e_state.es_expr_heap, hp_type_heaps = e_state.es_type_heaps } cs
-	  (es_fun_defs, cs_symbol_table) = removeLocalsFromSymbolTable ei_expr_level var_env let_locals es_fun_defs cs.cs_symbol_table
-	= (expr, free_vars,
-		{ e_state & es_fun_defs = es_fun_defs, es_var_heap = heaps.hp_var_heap, es_expr_heap = heaps.hp_expression_heap,
-			es_type_heaps = heaps.hp_type_heaps }, e_info, { cs & cs_symbol_table = cs_symbol_table })
-
-checkExpression free_vars (PE_Case case_ident expr alts) e_input e_state e_info cs
-	# (pattern_expr, free_vars, e_state, e_info, cs) = checkExpression free_vars expr e_input e_state e_info cs
-	  (guards, _, pattern_variables, defaul, free_vars, e_state, e_info, cs) = check_guarded_expressions free_vars alts [] case_ident.id_name e_input e_state e_info cs
-	  (pattern_expr, binds, es_expr_heap) = bind_pattern_variables pattern_variables pattern_expr e_state.es_expr_heap
-	  (case_expr, es_expr_heap) = build_case guards defaul pattern_expr case_ident es_expr_heap
-	  (result_expr, es_expr_heap) = buildLetExpression [] binds case_expr NoPos es_expr_heap
-	= (result_expr, free_vars, { e_state & es_expr_heap = es_expr_heap }, e_info, cs)
-	
-where
-	check_guarded_expressions free_vars [g] pattern_variables case_name e_input=:{ei_expr_level} e_state e_info cs
-		# e_input = { e_input & ei_expr_level = inc ei_expr_level }
-		= check_guarded_expression free_vars g NoPattern NoPattern pattern_variables No case_name e_input e_state e_info cs 
-	check_guarded_expressions free_vars [g : gs] pattern_variables case_name e_input=:{ei_expr_level} e_state e_info cs
-		# e_input = { e_input & ei_expr_level = inc ei_expr_level }
-		  (gs, pattern_scheme, pattern_variables, defaul, free_vars, e_state, e_info, cs)
-		  	= check_guarded_expressions free_vars gs pattern_variables case_name e_input e_state e_info cs
-		= check_guarded_expression free_vars g gs pattern_scheme pattern_variables defaul case_name e_input e_state e_info cs 
-	check_guarded_expression free_vars {calt_pattern,calt_rhs={rhs_alts,rhs_locals}} patterns pattern_scheme pattern_variables defaul case_name 
-				e_input=:{ei_expr_level,ei_mod_index} e_state=:{es_fun_defs,es_var_heap} e_info cs
-		# (pattern, (var_env, array_patterns), {ps_fun_defs,ps_var_heap}, e_info, cs)
-				= checkPattern calt_pattern No { pi_def_level = ei_expr_level, pi_mod_index = ei_mod_index, pi_is_node_pattern = False } ([], [])
-					{ps_var_heap = es_var_heap, ps_fun_defs = es_fun_defs} e_info cs
-		  e_state = { e_state & es_var_heap = ps_var_heap, es_fun_defs = ps_fun_defs }
-		  (rhs_expr, free_vars, e_state, e_info, cs)
-		  		= checkRhs free_vars rhs_alts rhs_locals e_input e_state e_info cs
-		  (expr_with_array_selections, free_vars, e_state=:{es_dynamics,es_expr_heap,es_var_heap}, e_info, cs)
-				= addArraySelections array_patterns rhs_expr free_vars e_input e_state e_info cs
-		  cs_symbol_table = removeLocalIdentsFromSymbolTable ei_expr_level var_env cs.cs_symbol_table
-		  (guarded_expr, pattern_scheme, pattern_variables, defaul, es_var_heap, es_expr_heap, dynamics_in_patterns, cs)
-		  		= transform_pattern pattern patterns pattern_scheme pattern_variables defaul expr_with_array_selections case_name
-		  									es_var_heap es_expr_heap es_dynamics { cs & cs_symbol_table = cs_symbol_table }
-		= (guarded_expr, pattern_scheme, pattern_variables, defaul, free_vars,
-			{ e_state & es_var_heap = es_var_heap, es_expr_heap = es_expr_heap, es_dynamics = dynamics_in_patterns },
-				e_info, cs)
-
-	transform_pattern :: !AuxiliaryPattern !CasePatterns !CasePatterns !(Env Ident VarInfoPtr) !(Optional (!Optional FreeVar, !Expression)) !Expression
-			!String !*VarHeap !*ExpressionHeap ![DynamicPtr] !*CheckState
-				-> (!CasePatterns, !CasePatterns, !Env Ident VarInfoPtr, !Optional (!Optional FreeVar,!Expression), !*VarHeap, !*ExpressionHeap, ![DynamicPtr], !*CheckState)
-	transform_pattern (AP_Algebraic cons_symbol type_index args opt_var) patterns pattern_scheme pattern_variables defaul result_expr _ var_store expr_heap opt_dynamics cs
-		# (var_args, result_expr, _, var_store, expr_heap, opt_dynamics, cs) = convertSubPatterns args result_expr NoPos var_store expr_heap opt_dynamics cs
-		  type_symbol = { glob_module = cons_symbol.glob_module, glob_object = type_index}
-		  pattern = { ap_symbol = cons_symbol, ap_vars = var_args, ap_expr = result_expr, ap_position = NoPos}
-		  pattern_variables = cons_optional opt_var pattern_variables
-		= case pattern_scheme of
-			AlgebraicPatterns alg_type _
-				| type_symbol == alg_type
-					# alg_patterns = case patterns of
-							AlgebraicPatterns _ alg_patterns -> alg_patterns
-							NoPattern -> []
-					-> (AlgebraicPatterns type_symbol [pattern : alg_patterns], pattern_scheme, pattern_variables, defaul, var_store, expr_heap, opt_dynamics, cs)
-					-> (patterns, pattern_scheme, pattern_variables, defaul, var_store, expr_heap, opt_dynamics,
-								{ cs & cs_error = checkError cons_symbol.glob_object.ds_ident "incompatible types of patterns" cs.cs_error })
-			NoPattern
-				-> (AlgebraicPatterns type_symbol [pattern], AlgebraicPatterns type_symbol [], pattern_variables, defaul, var_store, expr_heap, opt_dynamics, cs)
-			_
-				-> (patterns, pattern_scheme, pattern_variables, defaul, var_store, expr_heap, opt_dynamics,
-						{ cs & cs_error = checkError cons_symbol.glob_object.ds_ident "illegal combination of patterns" cs.cs_error })
-	transform_pattern (AP_Basic basic_val opt_var) patterns pattern_scheme pattern_variables defaul result_expr _ var_store expr_heap opt_dynamics cs
-		# pattern = { bp_value = basic_val, bp_expr = result_expr, bp_position = NoPos}
-		  pattern_variables = cons_optional opt_var pattern_variables
-		  (type_symbol, cs) = typeOfBasicValue basic_val cs
-		= case pattern_scheme of
-			BasicPatterns basic_type _
-				| type_symbol == basic_type
-					# basic_patterns = case patterns of
-							BasicPatterns _ basic_patterns
-								-> basic_patterns
-							NoPattern
-								-> [] 
-					-> (BasicPatterns basic_type [pattern : basic_patterns], pattern_scheme, pattern_variables, defaul, var_store, expr_heap, opt_dynamics, cs)
-					-> (patterns, pattern_scheme, pattern_variables, defaul, var_store, expr_heap, opt_dynamics,
-							{ cs & cs_error = checkError basic_val "incompatible types of patterns" cs.cs_error })
-			NoPattern
-				-> (BasicPatterns type_symbol [pattern], BasicPatterns type_symbol [], pattern_variables, defaul, var_store, expr_heap, opt_dynamics, cs)
-			_
-				-> (patterns, pattern_scheme, pattern_variables, defaul, var_store, expr_heap, opt_dynamics,
-						{ cs & cs_error = checkError basic_val "illegal combination of patterns" cs.cs_error})
-	transform_pattern (AP_Dynamic pattern type opt_var) patterns pattern_scheme pattern_variables defaul result_expr _ var_store expr_heap opt_dynamics cs
-		# (var_arg, result_expr, _, var_store, expr_heap, opt_dynamics, cs) = convertSubPattern pattern result_expr NoPos var_store expr_heap opt_dynamics cs
-		  (dynamic_info_ptr, expr_heap) = newPtr (EI_DynamicType type opt_dynamics) expr_heap
-		  pattern = { dp_var = var_arg, dp_type	= dynamic_info_ptr,	dp_rhs = result_expr, dp_type_patterns_vars = [],
-		  				dp_type_code = TCE_Empty, dp_position = NoPos }
-		  pattern_variables = cons_optional opt_var pattern_variables
-		= case pattern_scheme of
-			DynamicPatterns _
-				# dyn_patterns = case patterns of 
-										DynamicPatterns dyn_patterns
-											-> dyn_patterns
-										NoPattern
-											-> []
-				-> (DynamicPatterns [pattern : dyn_patterns], pattern_scheme, pattern_variables, defaul, var_store, expr_heap, [dynamic_info_ptr], cs)
-			NoPattern
-				-> (DynamicPatterns [pattern], DynamicPatterns [], pattern_variables, defaul, var_store, expr_heap, [dynamic_info_ptr], cs)
-			_
-				-> (patterns, pattern_scheme, pattern_variables, defaul, var_store, expr_heap, opt_dynamics,
-						{ cs & cs_error = checkError "<dynamic pattern>" "illegal combination of patterns" cs.cs_error })
-	transform_pattern (AP_Variable name var_info opt_var) NoPattern pattern_scheme pattern_variables No result_expr _ var_store expr_heap opt_dynamics cs
-		= ( NoPattern, pattern_scheme, cons_optional opt_var pattern_variables, 
-		  	Yes (Yes { fv_name = name, fv_info_ptr = var_info, fv_def_level = NotALevel, fv_count = 0 }, result_expr),
-			var_store, expr_heap, opt_dynamics, cs)		
-	transform_pattern (AP_Variable name var_info opt_var) patterns pattern_scheme pattern_variables defaul result_expr case_name var_store expr_heap opt_dynamics cs
-		# free_var = { fv_name = name, fv_info_ptr = var_info, fv_def_level = NotALevel, fv_count = 0 }
-		  (new_bound_var, expr_heap) = allocate_bound_var free_var expr_heap
-		  case_ident = { id_name = case_name, id_info = nilPtr }
-		  (new_case, expr_heap) = build_case patterns defaul (Var new_bound_var) case_ident expr_heap
-		  new_defaul = insert_as_default new_case result_expr
-		= (NoPattern, pattern_scheme, (cons_optional opt_var pattern_variables), Yes (Yes free_var, new_defaul),
-			var_store, expr_heap, opt_dynamics, cs)
-	transform_pattern (AP_WildCard (Yes opt_var)) patterns pattern_scheme pattern_variables defaul result_expr case_name var_store expr_heap opt_dynamics cs
-		= transform_pattern (AP_Variable opt_var.bind_src opt_var.bind_dst No) patterns pattern_scheme pattern_variables defaul
-							result_expr case_name var_store expr_heap opt_dynamics cs
-	transform_pattern (AP_WildCard no) NoPattern pattern_scheme pattern_variables No result_expr _ var_store expr_heap opt_dynamics cs
-		= (NoPattern, pattern_scheme, pattern_variables, Yes (No, result_expr), var_store, expr_heap, opt_dynamics, cs)
-	transform_pattern (AP_WildCard _) patterns pattern_scheme pattern_variables defaul result_expr case_name var_store expr_heap opt_dynamics cs
-		# (new_info_ptr, var_store) = newPtr VI_Empty var_store
-		= transform_pattern (AP_Variable (newVarId "wc") new_info_ptr No) patterns pattern_scheme pattern_variables defaul
-							result_expr case_name var_store expr_heap opt_dynamics cs
-	transform_pattern (AP_Empty name) patterns pattern_scheme pattern_variables defaul result_expr _ var_store expr_heap opt_dynamics cs
-		= (patterns, pattern_scheme, pattern_variables, defaul, var_store, expr_heap, opt_dynamics, cs)
-
-
-	insert_as_default :: !Expression !Expression -> Expression
-	insert_as_default to_insert (Let lad=:{let_expr})
-		= Let { lad & let_expr = insert_as_default to_insert let_expr }
-	insert_as_default to_insert (Case kees=:{case_default})
-		= case case_default of
-			No			-> Case { kees & case_default = Yes to_insert }
-			Yes defaul	-> Case { kees & case_default = Yes (insert_as_default to_insert defaul)}
-	insert_as_default _ expr = expr // checkWarning "pattern won't match"
-
-	build_case NoPattern defaul expr case_ident expr_heap
-		= case defaul of
-			Yes (opt_var, result)
-				-> case opt_var of
-					Yes var
-						# (let_expression, expr_heap) = bind_default_variable expr var result expr_heap
-						-> (let_expression, expr_heap)
-					No
-						-> (result, expr_heap)
-			No
-				-> (EE, expr_heap)
-	build_case (DynamicPatterns patterns) defaul expr case_ident expr_heap
-		= case defaul of
-			Yes (opt_var, result)
-				-> case opt_var of
-					Yes var
-						# (type_case_info_ptr, expr_heap) = newPtr EI_Empty expr_heap
-						  (bound_var, expr_heap) = allocate_bound_var var expr_heap
-						  result = buildTypeCase (Var bound_var) patterns (Yes result) type_case_info_ptr
-						  (case_expression, expr_heap) = bind_default_variable expr var result expr_heap
-					 	-> (case_expression, expr_heap)
-					No
-						# (type_case_info_ptr, expr_heap) = newPtr EI_Empty expr_heap
-						-> (buildTypeCase expr patterns (Yes result) type_case_info_ptr, expr_heap)
-			No
-				# (type_case_info_ptr, expr_heap) = newPtr EI_Empty expr_heap
-				-> (buildTypeCase expr patterns No type_case_info_ptr, expr_heap)
-	build_case patterns (Yes (opt_var,result)) expr case_ident expr_heap
-		= case opt_var of
-			Yes var
-				# (case_expr_ptr, expr_heap) = newPtr EI_Empty expr_heap
-				  (bound_var, expr_heap) = allocate_bound_var var expr_heap
-				  result = Case {case_expr = Var bound_var, case_guards = patterns, case_default = Yes result,
-								 case_ident = Yes case_ident, case_info_ptr = case_expr_ptr,
-								 case_default_pos = NoPos }
-				  (case_expression, expr_heap) = bind_default_variable expr var result expr_heap
-				-> (case_expression, expr_heap)
-			No
-				#  (case_expr_ptr, expr_heap) = newPtr EI_Empty expr_heap
-				-> (Case {case_expr = expr, case_guards = patterns, case_default = Yes result,
-						case_ident = Yes case_ident, case_info_ptr = case_expr_ptr, case_default_pos = NoPos }, expr_heap)
-	build_case patterns No expr case_ident expr_heap
-		# (case_expr_ptr, expr_heap) = newPtr EI_Empty expr_heap
-		= (Case {case_expr = expr, case_guards = patterns, case_default = No, case_ident = Yes case_ident,
-			case_info_ptr = case_expr_ptr, case_default_pos = NoPos }, expr_heap)
-
-	bind_default_variable lb_src lb_dst result_expr expr_heap
-		#  (let_expr_ptr, expr_heap) = newPtr EI_Empty expr_heap
-		= (Let {let_strict_binds = [], let_lazy_binds = [{ lb_src = lb_src, lb_dst = lb_dst, lb_position = NoPos }],
-				let_expr = result_expr, let_info_ptr = let_expr_ptr, let_expr_position = NoPos }, expr_heap)
-
-	bind_pattern_variables [] pattern_expr expr_heap
-		= (pattern_expr, [], expr_heap)
-	bind_pattern_variables [{bind_src,bind_dst} : variables] this_pattern_expr expr_heap
-		# free_var = { fv_name = bind_src, fv_info_ptr = bind_dst, fv_def_level = NotALevel, fv_count = 0 }
-		  (bound_var, expr_heap) = allocate_bound_var free_var expr_heap
-		  (pattern_expr, binds, expr_heap) = bind_pattern_variables variables (Var bound_var) expr_heap
-		= (pattern_expr, [{lb_src = this_pattern_expr, lb_dst = free_var, lb_position = NoPos } : binds], expr_heap)
-
-	cons_optional (Yes var) variables
-		= [ var : variables ]
-	cons_optional No variables
-		= variables
-
-checkExpression free_vars (PE_Selection is_unique expr [PS_Array index_expr]) e_input e_state e_info cs	
-	# (expr, free_vars, e_state, e_info, cs) = checkExpression free_vars expr e_input e_state e_info cs
-	| is_unique
-		# (glob_select_symb, cs) = getPredefinedGlobalSymbol PD_UnqArraySelectFun PD_StdArray STE_Member 2 cs
-		  (selector, free_vars, e_state, e_info, cs) = checkArraySelection glob_select_symb free_vars index_expr e_input e_state e_info cs
-		= (Selection No expr [selector], free_vars, e_state, e_info, cs)
-		# (glob_select_symb, cs) = getPredefinedGlobalSymbol PD_ArraySelectFun PD_StdArray STE_Member 2 cs
-		  (selector, free_vars, e_state, e_info, cs) = checkArraySelection glob_select_symb free_vars index_expr e_input e_state e_info cs
-		= (Selection No expr [selector], free_vars, e_state, e_info, cs)
-checkExpression free_vars (PE_Selection is_unique expr selectors) e_input e_state e_info cs	
-	# (selectors, free_vars, e_state, e_info, cs) = checkSelectors cEndWithSelection free_vars selectors e_input e_state e_info cs
-	  (expr, free_vars, e_state, e_info, cs) = checkExpression free_vars expr e_input e_state e_info cs
-	| is_unique
-		# (tuple_type, cs) = getPredefinedGlobalSymbol (GetTupleTypeIndex 2) PD_PredefinedModule STE_Type 2 cs
-		= (Selection (Yes tuple_type) expr selectors, free_vars, e_state, e_info, cs)
-		= (Selection No expr selectors, free_vars, e_state, e_info, cs)
-checkExpression free_vars (PE_Update expr1 selectors expr2) e_input e_state e_info cs	
-	# (expr1, free_vars, e_state, e_info, cs) = checkExpression free_vars expr1 e_input e_state e_info cs
-	  (selectors, free_vars, e_state, e_info, cs) = checkSelectors cEndWithUpdate free_vars selectors e_input e_state e_info cs
-	  (expr2, free_vars, e_state, e_info, cs) = checkExpression free_vars expr2 e_input e_state e_info cs
-	= (Update expr1 selectors expr2, free_vars, e_state, e_info, cs)
-checkExpression free_vars (PE_Tuple exprs) e_input e_state e_info cs
-	# (exprs, arity, free_vars, e_state, e_info, cs) = check_expression_list free_vars exprs e_input e_state e_info cs
-	  ({glob_object={ds_ident,ds_index, ds_arity},glob_module}, cs)
-	  		= getPredefinedGlobalSymbol (GetTupleConsIndex arity) PD_PredefinedModule STE_Constructor arity cs
-	= (App { app_symb = { symb_name = ds_ident, symb_arity = ds_arity,
-						  symb_kind = SK_Constructor { glob_object = ds_index, glob_module = glob_module }},
-			 app_args = exprs, app_info_ptr = nilPtr }, free_vars, e_state, e_info, cs)
-where
-	check_expression_list free_vars [] e_input e_state e_info cs
-		= ([], 0, free_vars, e_state, e_info, cs)
-	check_expression_list free_vars [expr : exprs] e_input e_state e_info cs
-		# (expr, free_vars, e_state, e_info, cs) = checkExpression free_vars expr e_input e_state e_info cs
-		  (exprs, length, free_vars, e_state, e_info, cs) = check_expression_list free_vars exprs e_input e_state e_info cs
-		= ([expr : exprs], inc length, free_vars, e_state, e_info, cs)
-
-checkExpression free_vars rec=:(PE_Record record opt_type fields) e_input=:{ei_expr_level,ei_mod_index} e_state e_info cs
-	# (opt_record_and_fields, e_info, cs) = checkFields ei_mod_index fields opt_type e_info cs
-	= case opt_record_and_fields of
-		Yes (cons=:{glob_module, glob_object}, _, new_fields)
-			# {ds_ident,ds_index,ds_arity} = glob_object
-			  rec_cons = { symb_name = ds_ident, symb_kind = SK_Constructor { glob_object = ds_index, glob_module = glob_module }, symb_arity = ds_arity }
-			-> case record of
-				PE_Empty
-					# (exprs, free_vars, e_state, e_info, cs) = check_field_exprs free_vars new_fields 0 RK_Constructor e_input e_state e_info cs
-					-> (App { app_symb = rec_cons, app_args = remove_fields exprs, app_info_ptr = nilPtr }, free_vars, e_state, e_info, cs)
-				_
-					# (rec_expr, free_vars, e_state, e_info, cs) = checkExpression free_vars record e_input e_state e_info cs
-					-> case rec_expr of
-						Var {var_info_ptr,var_name}
-							# (var_info, es_var_heap) = readPtr var_info_ptr e_state.es_var_heap
-							  e_state = { e_state & es_var_heap = es_var_heap }
-							-> case var_info of
-								VI_Record fields
-									# (exprs, free_vars, e_state, e_info, cs) 
-											= check_field_exprs free_vars new_fields 0 (RK_UpdateToConstructor fields) e_input e_state e_info cs
-									-> (App { app_symb = rec_cons, app_args = remove_fields exprs, app_info_ptr = nilPtr }, free_vars, e_state, e_info, cs)
-								_ 
-									# (exprs, free_vars, e_state, e_info, cs)
-											= check_field_exprs free_vars new_fields 0 RK_Update e_input e_state e_info cs
-									-> (RecordUpdate cons rec_expr exprs, free_vars, e_state, e_info, cs)
-						_ 
-							# (exprs, free_vars, e_state, e_info, cs)
-									= check_field_exprs free_vars new_fields 0 RK_Update e_input e_state e_info cs
-							-> (RecordUpdate cons rec_expr exprs, free_vars, e_state, e_info, cs)
-		No
-			-> (EE, free_vars, e_state, e_info, cs)
-where
-	remove_fields binds = [ bind_src \\ {bind_src} <- binds ]
-
-	check_field_exprs :: [FreeVar] [Bind ParsedExpr (Global FieldSymbol)] Int RecordKind ExpressionInput !*ExpressionState !*ExpressionInfo !*CheckState -> *(![.Bind Expression (Global FieldSymbol)],![FreeVar],!*ExpressionState,!*ExpressionInfo,!*CheckState);
-	check_field_exprs free_vars [] field_nr record_kind e_input e_state e_info cs
-		= ([], free_vars, e_state, e_info, cs)
-	check_field_exprs free_vars [field_expr : field_exprs] field_nr record_kind e_input e_state e_info cs
-		# (expr, free_vars, e_state, e_info, cs)
-			= check_field_expr free_vars field_expr field_nr record_kind e_input e_state e_info cs
-		  (exprs, free_vars, e_state, e_info, cs) = check_field_exprs free_vars field_exprs (inc field_nr) record_kind e_input e_state e_info cs
-		= ([expr : exprs], free_vars, e_state, e_info, cs)
-
-	check_field_expr :: [FreeVar] (Bind ParsedExpr (Global FieldSymbol)) Int RecordKind ExpressionInput *ExpressionState *ExpressionInfo *CheckState -> *(!.Bind Expression (Global FieldSymbol),![FreeVar],!*ExpressionState,!*ExpressionInfo,!*CheckState);
-	check_field_expr free_vars field=:{bind_src = PE_Empty, bind_dst={glob_object={fs_var,fs_name,fs_index},glob_module}} field_nr record_kind e_input e_state e_info cs
-		# (expr, free_vars, e_state, e_info, cs)
-			= checkIdentExpression cIsNotInExpressionList free_vars fs_var e_input e_state e_info cs
-		= ({ field & bind_src = expr }, free_vars, e_state, e_info, cs)
-	check_field_expr free_vars field=:{bind_src = PE_WildCard, bind_dst={glob_object=fs_name}} field_nr RK_Constructor e_input e_state e_info cs
-		= ({ field & bind_src = NoBind nilPtr }, free_vars, e_state, e_info, { cs & cs_error = checkError fs_name "field not specified" cs.cs_error })
-	check_field_expr free_vars field=:{bind_src = PE_WildCard} field_nr RK_Update e_input e_state=:{es_expr_heap} e_info cs
-		# (bind_expr_ptr, es_expr_heap) = newPtr EI_Empty es_expr_heap
-		= ({ field & bind_src = NoBind bind_expr_ptr }, free_vars, { e_state & es_expr_heap = es_expr_heap }, e_info, cs)
-	check_field_expr free_vars field=:{bind_src = PE_WildCard} field_nr (RK_UpdateToConstructor fields) e_input e_state=:{es_expr_heap} e_info cs
-		# (var_name, var_info_ptr) = get_field_var (fields !! field_nr)
-		  (var_expr_ptr, es_expr_heap) = newPtr EI_Empty es_expr_heap
-		= ({ field & bind_src = Var { var_name = var_name, var_info_ptr = var_info_ptr, var_expr_ptr = var_expr_ptr }}, free_vars,
-				{ e_state & es_expr_heap = es_expr_heap }, e_info, cs)
-	check_field_expr free_vars field=:{bind_src} field_nr upd_record e_input e_state e_info cs
-		# (expr, free_vars, e_state, e_info, cs)
-			= checkExpression free_vars bind_src e_input e_state e_info cs
-		= ({ field & bind_src = expr }, free_vars, e_state, e_info, cs)
-	
-	get_field_var (AP_Algebraic _ _ _ (Yes {bind_src,bind_dst}))
-		= (bind_src, bind_dst)
-	get_field_var (AP_Basic _ (Yes {bind_src,bind_dst}))
-		= (bind_src, bind_dst)
-	get_field_var (AP_Dynamic _ _ (Yes {bind_src,bind_dst}))
-		= (bind_src, bind_dst)
-	get_field_var (AP_Variable id var_ptr _)
-		= (id, var_ptr)
-	get_field_var (AP_WildCard (Yes {bind_src,bind_dst}))
-		= (bind_src, bind_dst)
-	get_field_var _
-		= ({ id_name = "** ERRONEOUS **", id_info = nilPtr }, nilPtr)
-
-checkExpression free_vars (PE_Dynamic expr opt_type) e_input e_state=:{es_expr_heap,es_dynamics} e_info cs=:{cs_x}
-	# (dyn_info_ptr, es_expr_heap) = newPtr (EI_Dynamic opt_type) es_expr_heap
-	  (dyn_expr, free_vars, e_state, e_info, cs) = checkExpression free_vars expr e_input
-	  		{e_state & es_dynamics = [dyn_info_ptr : es_dynamics], es_expr_heap = es_expr_heap } e_info cs
-	= (DynamicExpr { dyn_expr = dyn_expr, dyn_opt_type = opt_type, dyn_info_ptr = dyn_info_ptr, dyn_type_code = TCE_Empty, dyn_uni_vars = [] },
-			free_vars, e_state, e_info, { cs & cs_x.x_needed_modules = cs_x.x_needed_modules bitor cNeedStdDynamics }) 
-
-checkExpression free_vars (PE_Basic basic_value) e_input e_state e_info cs
-	# (basic_type, cs) = typeOfBasicValue basic_value cs
-	= (BasicExpr basic_value basic_type, free_vars, e_state, e_info, cs)
-
-checkExpression free_vars (PE_ABC_Code code_sequence do_inline) e_input e_state e_info cs
-	= (ABCCodeExpr code_sequence do_inline, free_vars, e_state, e_info, cs)
-checkExpression free_vars (PE_Any_Code ins outs code_sequence) e_input e_state e_info cs
-	# (ins, (free_vars, e_state, e_info, cs)) = check_in_parameters e_input ins (free_vars, e_state, e_info, cs)
-	  (new_outs, (e_state, cs)) = check_out_parameters e_input.ei_expr_level outs (e_state, cs)
-	  cs_symbol_table = remove_out_parameters_from_symbol_table e_input.ei_expr_level outs cs.cs_symbol_table
-	= (AnyCodeExpr ins new_outs code_sequence, free_vars, e_state, e_info, { cs & cs_symbol_table = cs_symbol_table })
-where
-	check_in_parameters e_input params fv_es_ei_cs
-		= mapSt (check_in_parameter e_input) params fv_es_ei_cs
-
-	check_in_parameter e_input { bind_src, bind_dst } (free_vars, e_state, e_info, cs)
-		# (id_expr, free_vars, e_state, e_info, cs) = checkIdentExpression cIsNotInExpressionList free_vars bind_dst e_input e_state e_info cs
-		= case id_expr of
-			Var var
-				-> ({ bind_dst = var, bind_src = bind_src }, (free_vars, e_state, e_info, cs))
-			_
-				-> ({ bind_dst = { var_name = bind_dst, var_info_ptr = nilPtr, var_expr_ptr = nilPtr }, bind_src = bind_src }, (free_vars, e_state, e_info,
-						{ cs & cs_error = checkError bind_src "bound variable expected" cs.cs_error }))
-
-	check_out_parameters expr_level params es_cs
-		= mapSt (check_out_parameter expr_level) params es_cs
-
-	check_out_parameter expr_level bind=:{ bind_src, bind_dst } (e_state, cs)
-		| isLowerCaseName bind_dst.id_name
-			# (entry, cs_symbol_table) = readPtr bind_dst.id_info cs.cs_symbol_table
-			# (new_info_ptr, es_var_heap) = newPtr VI_Empty e_state.es_var_heap
-			  cs = checkPatternVariable expr_level entry bind_dst new_info_ptr { cs & cs_symbol_table = cs_symbol_table }
-			= (	{ bind & bind_dst = { fv_def_level = expr_level, fv_name = bind_dst, fv_info_ptr = new_info_ptr, fv_count = 0 }},
-					( { e_state & es_var_heap = es_var_heap }, cs))
-			= ( { bind & bind_dst = { fv_def_level = expr_level, fv_name = bind_dst, fv_info_ptr = nilPtr, fv_count = 0 }},
-					( e_state, { cs & cs_error = checkError bind_src "variable expected" cs.cs_error }))
-
-	remove_out_parameters_from_symbol_table expr_level idents symbol_table
-		= foldSt (\{bind_dst} -> removeIdentFromSymbolTable expr_level bind_dst) idents symbol_table
-
-checkExpression free_vars (PE_Ident id) e_input e_state e_info cs
-	= checkIdentExpression cIsNotInExpressionList free_vars id e_input e_state e_info cs
-checkExpression free_vars expr e_input e_state e_info cs
-	= abort "checkExpression (check.icl, line 1433)" // <<- expr
-
-:: LastSelection	= LS_Update | LS_Selction | LS_UniqueSelection
- 
-checkSelectors end_with_update free_vars [ selector : selectors ] e_input e_state e_info cs
-	| isEmpty selectors
-		# (selector, free_vars, e_state, e_info, cs) = check_selector end_with_update free_vars selector e_input e_state e_info cs
-		= ([ selector ], free_vars, e_state, e_info, cs)
-		# (selector, free_vars, e_state, e_info, cs) = check_selector cEndWithSelection free_vars selector e_input e_state e_info cs
-		  (selectors, free_vars, e_state, e_info, cs) = checkSelectors end_with_update free_vars selectors e_input e_state e_info cs
-		= ([ selector : selectors ], free_vars, e_state, e_info, cs)
-where		
-	check_selector _ free_vars (PS_Record selector=:{id_info,id_name} opt_type) e_input=:{ei_mod_index} e_state
-			e_info=:{ef_selector_defs, ef_modules} cs=:{cs_symbol_table}
-		# (entry, cs_symbol_table) = readPtr id_info cs_symbol_table
-		# selectors = retrieveSelectorIndexes ei_mod_index entry 
-		  (field_module, field_index, field_nr, ef_selector_defs, ef_modules, cs)
-		  		= get_field_nr ei_mod_index selector opt_type selectors ef_selector_defs ef_modules { cs & cs_symbol_table = cs_symbol_table }
-		= (RecordSelection { glob_object = MakeDefinedSymbol selector field_index 1, glob_module = field_module } field_nr, free_vars, e_state,
-								{e_info & ef_selector_defs = ef_selector_defs, ef_modules = ef_modules }, cs)
-	where					
-		get_field_nr :: !Index !Ident !(Optional Ident) ![Global Index] !u:{#SelectorDef} !v:{# DclModule} !*CheckState
-				-> (!Index, !Index, !Index, u:{#SelectorDef}, v:{#DclModule}, !*CheckState)
-		get_field_nr mod_index sel_id _ [] selector_defs modules cs=:{cs_error}
-			= (NoIndex, NoIndex, NoIndex, selector_defs, modules, { cs & cs_error = checkError id_name " selector not defined" cs_error })
-		get_field_nr mod_index sel_id (Yes type_id=:{id_info}) selectors selector_defs modules cs=:{cs_symbol_table,cs_error}
-			# (entry, cs_symbol_table) = readPtr id_info cs_symbol_table
-			# (type_index, type_module) = retrieveGlobalDefinition entry STE_Type mod_index
-			| type_index <> NotFound
-				# (selector_index, selector_offset, selector_defs, modules)
-						= determine_selector mod_index type_module type_index selectors selector_defs modules
-				| selector_offset <> NoIndex
-					= (type_module, selector_index, selector_offset, selector_defs, modules, { cs & cs_symbol_table = cs_symbol_table })
-					= (NoIndex, NoIndex, NoIndex, selector_defs, modules, { cs & cs_symbol_table = cs_symbol_table,
-								cs_error = checkError id_name " selector not defined" cs_error })
-				= (NoIndex, NoIndex, NoIndex, selector_defs, modules, { cs & cs_symbol_table = cs_symbol_table,
-						cs_error = checkError type_id " type not defined" cs_error })
-		get_field_nr mod_index sel_id No [{glob_object,glob_module}] selector_defs modules cs
-			| mod_index == glob_module
-				# (selector_offset,selector_defs) = selector_defs![glob_object].sd_field_nr
-				= (glob_module, glob_object, selector_offset, selector_defs, modules, cs)
-				# (selector_offset,modules) = modules![glob_module].dcl_common.com_selector_defs.[glob_object].sd_field_nr
-				= (glob_module, glob_object, selector_offset, selector_defs, modules, cs)
-		get_field_nr mod_index sel_id No _  selector_defs modules cs=:{cs_error}
-			= (NoIndex, NoIndex, NoIndex, selector_defs, modules, { cs & cs_error = checkError sel_id " ambiguous selector specified" cs_error })
-
-		determine_selector :: !Index !Index !Index ![Global Index] !u:{# SelectorDef} !v:{# DclModule} -> (!Int, !Int, !u:{# SelectorDef}, !v:{# DclModule})
-		determine_selector mod_index type_mod_index type_index [] selector_defs modules
-			= (NoIndex, NoIndex, selector_defs, modules)
-		determine_selector mod_index type_mod_index type_index [{glob_module, glob_object} : selectors] selector_defs modules
-			| type_mod_index == glob_module
-				| type_mod_index == mod_index
-					#! selector_def = selector_defs.[glob_object]
-					| selector_def.sd_type_index == type_index
-						= (glob_object, selector_def.sd_field_nr, selector_defs, modules)
-						= determine_selector mod_index type_mod_index type_index selectors selector_defs modules
-					#! {dcl_common={com_selector_defs}} = modules.[glob_module]
-					#! selector_def = com_selector_defs.[glob_object]
-					| selector_def.sd_type_index == type_index
-						= (glob_object, selector_def.sd_field_nr, selector_defs, modules)
-						= determine_selector mod_index type_mod_index type_index selectors selector_defs modules
-				= determine_selector mod_index type_mod_index type_index selectors selector_defs modules
-
-	check_selector end_with_update free_vars (PS_Array index_expr) e_input e_state e_info cs
-		| end_with_update
-			# (glob_select_symb, cs) = getPredefinedGlobalSymbol PD_ArrayUpdateFun PD_StdArray STE_Member 3 cs
-			= checkArraySelection glob_select_symb free_vars index_expr e_input e_state e_info cs
-			# (glob_select_symb, cs) = getPredefinedGlobalSymbol PD_ArraySelectFun PD_StdArray STE_Member 2 cs
-			= checkArraySelection glob_select_symb free_vars index_expr e_input e_state e_info cs
-
-checkArraySelection glob_select_symb free_vars index_expr e_input e_state e_info cs
-	# (index_expr, free_vars, e_state, e_info, cs) = checkExpression free_vars index_expr e_input e_state e_info cs
-	  (new_info_ptr, es_expr_heap) = newPtr EI_Empty e_state.es_expr_heap
-	= (ArraySelection glob_select_symb new_info_ptr index_expr, free_vars, { e_state & es_expr_heap = es_expr_heap }, e_info, cs)
-
-buildLetExpression :: ![LetBind] ![LetBind] !Expression !Position !*ExpressionHeap  -> (!Expression, !*ExpressionHeap)
-buildLetExpression [] [] expr _ expr_heap
-	= (expr, expr_heap)
-buildLetExpression let_strict_binds let_lazy_binds expr let_expr_position expr_heap
-	# (let_expr_ptr, expr_heap) = newPtr EI_Empty expr_heap
-	= (Let {let_strict_binds = let_strict_binds, let_lazy_binds = let_lazy_binds, let_expr = expr,
-			let_info_ptr = let_expr_ptr, let_expr_position = let_expr_position }, expr_heap)
-
-checkLhssOfLocalDefs :: .Int .Int LocalDefs *ExpressionState *ExpressionInfo *CheckState -> (!.[NodeDef AuxiliaryPattern],!(![Ident],![ArrayPattern]),!.ExpressionState,!.ExpressionInfo,!.CheckState);
-checkLhssOfLocalDefs def_level mod_index (CollectedLocalDefs {loc_functions={ir_from,ir_to},loc_nodes}) e_state=:{es_var_heap,es_fun_defs} e_info cs
-	# (loc_defs, accus, {ps_fun_defs,ps_var_heap}, e_info, cs)
-			= check_patterns loc_nodes {pi_def_level = def_level, pi_mod_index = mod_index, pi_is_node_pattern = True } ([], [])
-					{ps_fun_defs = es_fun_defs, ps_var_heap = es_var_heap} e_info cs
-	  (es_fun_defs, cs_symbol_table, cs_error) = addLocalFunctionDefsToSymbolTable def_level ir_from ir_to ps_fun_defs cs.cs_symbol_table cs.cs_error
-	= (loc_defs, accus, { e_state & es_fun_defs = es_fun_defs, es_var_heap = ps_var_heap }, e_info, { cs & cs_symbol_table = cs_symbol_table, cs_error = cs_error })
-where
-	check_patterns [ (_,node_def) : node_defs ] p_input accus var_store e_info cs
-		# (pattern, accus, var_store, e_info, cs) = checkPattern node_def.nd_dst No p_input accus var_store e_info cs
-		  (patterns, accus, var_store, e_info, cs) = check_patterns node_defs p_input accus var_store e_info cs
-		= ([{ node_def & nd_dst = pattern } : patterns], accus, var_store, e_info, cs)
-	check_patterns [] p_input accus var_store e_info cs
-		= ([], accus, var_store, e_info, cs)
-
-checkRhssAndTransformLocalDefs free_vars [] rhs_expr e_input e_state e_info cs
-	= (rhs_expr, free_vars, e_state, e_info, cs)
-checkRhssAndTransformLocalDefs free_vars loc_defs rhs_expr e_input e_state e_info cs
-	# (binds, free_vars, e_state, e_info, cs) = checkAndTransformPatternIntoBind free_vars loc_defs e_input e_state e_info cs
-	  (rhs_expr, es_expr_heap) = buildLetExpression [] binds rhs_expr NoPos e_state.es_expr_heap
-	= (rhs_expr, free_vars, { e_state & es_expr_heap = es_expr_heap }, e_info, cs)
-
-checkAndTransformPatternIntoBind free_vars [{nd_dst,nd_alts,nd_locals,nd_position} : local_defs] e_input=:{ei_expr_level,ei_mod_index} e_state e_info cs
-	# cs = pushErrorAdmin (newPosition {id_name="node definition", id_info=nilPtr} nd_position) cs
-	# (bind_src, free_vars, e_state, e_info, cs) = checkRhs free_vars nd_alts nd_locals e_input e_state e_info cs	
-	  (binds_of_bind, es_var_heap, es_expr_heap, e_info, cs)
-			= transfromPatternIntoBind ei_mod_index ei_expr_level nd_dst bind_src nd_position
-				e_state.es_var_heap e_state.es_expr_heap e_info cs
-	  e_state = { e_state & es_var_heap = es_var_heap, es_expr_heap = es_expr_heap }
-	  (binds_of_local_defs, free_vars, e_state, e_info, cs) = checkAndTransformPatternIntoBind free_vars local_defs e_input e_state e_info cs
-	= (binds_of_bind ++ binds_of_local_defs, free_vars, e_state, e_info, popErrorAdmin cs)
-checkAndTransformPatternIntoBind free_vars [] e_input e_state e_info cs
-	= ([], free_vars, e_state, e_info, cs)
-
-transfromPatternIntoBind :: !Index !Level !AuxiliaryPattern !Expression !Position !*VarHeap !*ExpressionHeap !*ExpressionInfo !*CheckState
-	-> *(![LetBind], !*VarHeap, !*ExpressionHeap,  !*ExpressionInfo, !*CheckState)
-transfromPatternIntoBind mod_index def_level (AP_Variable name var_info _) src_expr position var_store expr_heap e_info cs
-	# bind = {lb_src = src_expr, lb_dst = { fv_name = name, fv_info_ptr = var_info, fv_def_level = def_level, fv_count = 0 }, lb_position = position }
-	= ([bind], var_store, expr_heap, e_info, cs)
-transfromPatternIntoBind mod_index def_level (AP_Algebraic cons_symbol=:{glob_module,glob_object=ds_cons=:{ds_arity, ds_index, ds_ident}} type_index args opt_var)
-		src_expr position var_store expr_heap e_info=:{ef_type_defs,ef_modules} cs
-	# (src_expr, opt_var_bind, var_store, expr_heap) = bind_opt_var opt_var src_expr position var_store expr_heap
-	| ds_arity == 0
-		= ([], var_store, expr_heap, e_info, { cs & cs_error = checkError ds_ident " constant not allowed in a node pattern" cs.cs_error})
-	# (is_tuple, cs) = is_tuple_symbol glob_module ds_index cs
-	| is_tuple
-		# (tuple_var, tuple_bind, var_store, expr_heap) = bind_match_expr src_expr opt_var_bind position var_store expr_heap
-		= transform_sub_patterns mod_index def_level args ds_cons 0 tuple_var tuple_bind position var_store expr_heap e_info cs
-		# ({td_rhs}, ef_type_defs, ef_modules) = get_type_def mod_index glob_module type_index ef_type_defs ef_modules
-		  e_info = { e_info & ef_type_defs = ef_type_defs, ef_modules = ef_modules }
-		= case td_rhs of
-			RecordType {rt_fields}
-				| size rt_fields == 1
-					-> transform_sub_patterns_of_record mod_index def_level args rt_fields glob_module 0
-							src_expr opt_var_bind position var_store expr_heap e_info cs
-					# (record_var, record_bind, var_store, expr_heap)
-						= bind_match_expr src_expr opt_var_bind position var_store expr_heap
-					-> transform_sub_patterns_of_record mod_index def_level args rt_fields glob_module 0
-							record_var record_bind position var_store expr_heap e_info cs
-			_
-				| ds_arity == 1
-		  			# (binds, var_store, expr_heap, e_info, cs)
-						= transfromPatternIntoBind mod_index def_level (hd args) (MatchExpr No cons_symbol src_expr)
-								position var_store expr_heap e_info cs
-					-> (opt_var_bind ++ binds, var_store, expr_heap, e_info, cs)
-					# (tuple_type, cs) = getPredefinedGlobalSymbol (GetTupleTypeIndex ds_arity) PD_PredefinedModule STE_Type ds_arity cs
-					  (tuple_cons, cs) = getPredefinedGlobalSymbol (GetTupleConsIndex ds_arity) PD_PredefinedModule STE_Constructor ds_arity cs
-					  (match_var, match_bind, var_store, expr_heap)
-						=  bind_match_expr (MatchExpr (Yes tuple_type) cons_symbol src_expr) opt_var_bind position var_store expr_heap
-					-> transform_sub_patterns mod_index def_level args tuple_cons.glob_object 0 match_var match_bind
-							position var_store expr_heap e_info cs
-
-
-where
-	get_type_def mod_index type_mod_index type_index ef_type_defs ef_modules
-		| mod_index == type_mod_index
-			# (type_def, ef_type_defs) = ef_type_defs![type_index]
-			= (type_def, ef_type_defs, ef_modules)
-			# ({dcl_common},  ef_modules) = ef_modules![type_mod_index]
-			= (dcl_common.com_type_defs.[type_index], ef_type_defs, ef_modules)
-		
-	is_tuple_symbol cons_module cons_index cs
-		# (tuple_2_symbol, cs) = getPredefinedGlobalSymbol (GetTupleConsIndex 2) PD_PredefinedModule STE_Constructor 2 cs
-		= (tuple_2_symbol.glob_module == cons_module &&
-		   tuple_2_symbol.glob_object.ds_index <= cons_index && cons_index <= tuple_2_symbol.glob_object.ds_index + 30, cs)
-
-	transform_sub_patterns mod_index def_level [pattern : patterns] tup_id tup_index arg_var all_binds position var_store expr_heap e_info cs
-		# (this_arg_var, expr_heap)
-				= adjust_match_expression arg_var expr_heap
-		  match_expr
-		  		= TupleSelect tup_id tup_index this_arg_var
-		  (binds, var_store, expr_heap, e_info, cs)
-		  		= transfromPatternIntoBind mod_index def_level pattern match_expr position var_store expr_heap e_info cs
-		= transform_sub_patterns mod_index def_level patterns tup_id (inc tup_index) arg_var (binds ++ all_binds)
-				position var_store expr_heap e_info cs
-	transform_sub_patterns mod_index _ [] _ _ _ binds _ var_store expr_heap e_info cs
-		= (binds, var_store, expr_heap, e_info, cs)
-
-	transform_sub_patterns_of_record mod_index def_level [pattern : patterns] fields field_module field_index record_expr
-			all_binds position var_store expr_heap e_info cs
-		# {fs_name, fs_index} = fields.[field_index]
-		  selector = { glob_module = field_module, glob_object = MakeDefinedSymbol fs_name fs_index 1}
-		  (this_record_expr, expr_heap) = adjust_match_expression record_expr expr_heap
-		  (binds, var_store, expr_heap, e_info, cs)
-				= transfromPatternIntoBind mod_index def_level pattern (Selection No this_record_expr [ RecordSelection selector field_index ])
-						position var_store expr_heap e_info cs
-		= transform_sub_patterns_of_record mod_index def_level patterns fields field_module (inc field_index) record_expr
-				(binds ++ all_binds) position var_store expr_heap e_info cs
-	transform_sub_patterns_of_record mod_index _ [] _ _ _ _ binds _ var_store expr_heap e_info cs
-		= (binds, var_store, expr_heap, e_info, cs)
-
-	bind_opt_var (Yes {bind_src,bind_dst}) src_expr position var_heap expr_heap
-		# free_var = { fv_name = bind_src, fv_info_ptr = bind_dst, fv_def_level = NotALevel, fv_count = 0 }
-		  (var_expr_ptr, expr_heap) = newPtr EI_Empty expr_heap
-		  bound_var = { var_name = bind_src, var_info_ptr = bind_dst, var_expr_ptr = var_expr_ptr }
-		= (Var bound_var, [{lb_src = src_expr, lb_dst = free_var, lb_position = position}], var_heap <:= (bind_dst, VI_Empty), expr_heap)
-	bind_opt_var No src_expr _ var_heap expr_heap
-		= (src_expr, [], var_heap, expr_heap)
-		
-	bind_match_expr var_expr=:(Var var) opt_var_bind _ var_heap expr_heap
-		= (var_expr, opt_var_bind, var_heap, expr_heap)
-	bind_match_expr match_expr opt_var_bind position var_heap expr_heap
-		# new_name = newVarId "_x"
-		  (var_info_ptr, var_heap) = newPtr VI_Empty var_heap
-//		  (var_expr_ptr, expr_heap) = newPtr EI_Empty expr_heap
-		  bound_var = { var_name = new_name, var_info_ptr = var_info_ptr, var_expr_ptr = nilPtr }
-		  free_var = { fv_name = new_name, fv_info_ptr = var_info_ptr, fv_def_level = def_level, fv_count = 0 }
-		= (Var bound_var, [{lb_src = match_expr, lb_dst = free_var, lb_position = position } : opt_var_bind], var_heap, expr_heap)
-
-	adjust_match_expression (Var var) expr_heap
-		# (var_expr_ptr, expr_heap) = newPtr EI_Empty expr_heap
-		= (Var { var & var_expr_ptr = var_expr_ptr }, expr_heap)
-	adjust_match_expression match_expr expr_heap
-		= (match_expr, expr_heap)
-
-transfromPatternIntoBind mod_index def_level (AP_WildCard _) src_expr _ var_store expr_heap e_info cs
-	= ([], var_store, expr_heap, e_info, cs)
-transfromPatternIntoBind _ _ pattern src_expr _ var_store expr_heap e_info cs
-	= ([], var_store, expr_heap, e_info, { cs & cs_error = checkError "<pattern>" " illegal node pattern" cs.cs_error})
-
-checkLocalFunctions mod_index level (CollectedLocalDefs {loc_functions={ir_from,ir_to}}) fun_defs e_info heaps cs
-	= checkFunctions mod_index level ir_from ir_to fun_defs e_info heaps cs
-
-// JVG: added type
-checkRhs :: [FreeVar] OptGuardedAlts LocalDefs ExpressionInput *ExpressionState *ExpressionInfo *CheckState -> *(!Expression,![FreeVar],!*ExpressionState,!*ExpressionInfo,!*CheckState);
-checkRhs free_vars rhs_alts rhs_locals e_input=:{ei_expr_level,ei_mod_index} e_state e_info cs
-	# ei_expr_level = inc ei_expr_level
-	  (loc_defs, (var_env, array_patterns), e_state, e_info, cs) = checkLhssOfLocalDefs ei_expr_level ei_mod_index rhs_locals e_state e_info cs
-	  (es_fun_defs, e_info, heaps, cs)
-	  		= checkLocalFunctions ei_mod_index ei_expr_level rhs_locals e_state.es_fun_defs e_info
-	  			{ hp_var_heap = e_state.es_var_heap, hp_expression_heap = e_state.es_expr_heap, hp_type_heaps = e_state.es_type_heaps } cs
-	  (rhs_expr, free_vars, e_state, e_info, cs) 
-	  		= check_opt_guarded_alts free_vars rhs_alts { e_input & ei_expr_level = ei_expr_level }
-	  			{ e_state & es_fun_defs = es_fun_defs, es_var_heap = heaps.hp_var_heap, es_expr_heap = heaps.hp_expression_heap,
-					es_type_heaps = heaps.hp_type_heaps } e_info cs
-	  (expr, free_vars, e_state, e_info, cs)
-			= addArraySelections array_patterns rhs_expr free_vars e_input e_state e_info cs
-	  (expr, free_vars, e_state, e_info, cs) = checkRhssAndTransformLocalDefs free_vars loc_defs expr e_input e_state e_info cs
-	  (es_fun_defs, cs_symbol_table) = removeLocalsFromSymbolTable ei_expr_level var_env rhs_locals e_state.es_fun_defs cs.cs_symbol_table
-	= (expr, free_vars, { e_state & es_fun_defs = es_fun_defs}, e_info, { cs & cs_symbol_table = cs_symbol_table })
-where
-	check_opt_guarded_alts free_vars (GuardedAlts guarded_alts default_expr) e_input e_state e_info cs
-		# (let_vars_list, rev_guarded_exprs, last_expr_level, free_vars, e_state, e_info, cs)
-				= check_guarded_expressions free_vars guarded_alts [] [] e_input e_state e_info cs
-		  (default_expr, free_vars, e_state, e_info, cs)
-		  		= check_default_expr free_vars default_expr { e_input & ei_expr_level = last_expr_level } e_state e_info cs
-		  cs = { cs & cs_symbol_table = remove_seq_let_vars e_input.ei_expr_level let_vars_list cs.cs_symbol_table }
-	  	  (_, result_expr, es_expr_heap) = convert_guards_to_cases rev_guarded_exprs default_expr e_state.es_expr_heap
-	  	= (result_expr, free_vars, { e_state & es_expr_heap = es_expr_heap }, e_info, cs)
-	check_opt_guarded_alts free_vars (UnGuardedExpr unguarded_expr) e_input e_state e_info cs
-		= check_unguarded_expression free_vars unguarded_expr e_input e_state e_info cs
-
-	check_default_expr free_vars (Yes default_expr) e_input e_state e_info cs
-		# (expr, free_vars, e_state, e_info, cs) = check_unguarded_expression free_vars default_expr e_input e_state e_info cs
-		= (Yes expr, free_vars, e_state, e_info, cs)
-	check_default_expr free_vars No e_input e_state e_info cs
-		= (No, free_vars, e_state, e_info, cs)
-		
-	convert_guards_to_cases [(let_binds, guard, expr, guard_ident)] result_expr es_expr_heap
-		# (case_expr_ptr, es_expr_heap) = newPtr EI_Empty es_expr_heap
-		  basic_pattern = {bp_value = (BVB True), bp_expr = expr, bp_position = NoPos }
-		  case_expr = Case { case_expr = guard, case_guards = BasicPatterns BT_Bool [basic_pattern],
-		  		case_default = result_expr, case_ident = Yes guard_ident,
-		  		case_info_ptr = case_expr_ptr, case_default_pos = NoPos }
-		= build_sequential_lets let_binds case_expr NoPos es_expr_heap
-	convert_guards_to_cases [(let_binds, guard, expr, guard_ident) : rev_guarded_exprs] result_expr es_expr_heap
-		# (case_expr_ptr, es_expr_heap) = newPtr EI_Empty es_expr_heap
-		  basic_pattern = {bp_value = (BVB True), bp_expr = expr, bp_position = NoPos }
-		  case_expr = Case { case_expr = guard, case_guards = BasicPatterns BT_Bool [basic_pattern],
-		  		case_default = result_expr, case_ident = Yes guard_ident,
-		  		case_info_ptr = case_expr_ptr, case_default_pos = NoPos }
-		  (_, result_expr, es_expr_heap) = build_sequential_lets let_binds case_expr NoPos es_expr_heap
-		= convert_guards_to_cases rev_guarded_exprs (Yes result_expr) es_expr_heap
-	
-	check_guarded_expressions free_vars [gexpr : gexprs] let_vars_list rev_guarded_exprs e_input e_state e_info cs
-		# (let_vars_list, rev_guarded_exprs, ei_expr_level, free_vars, e_state, e_info, cs)
-				= check_guarded_expression free_vars gexpr let_vars_list rev_guarded_exprs e_input e_state e_info cs
-		= check_guarded_expressions free_vars gexprs let_vars_list rev_guarded_exprs { e_input & ei_expr_level = ei_expr_level } e_state e_info cs
-	check_guarded_expressions free_vars [] let_vars_list rev_guarded_exprs {ei_expr_level} e_state e_info cs
-		= (let_vars_list, rev_guarded_exprs, ei_expr_level, free_vars, e_state, e_info, cs)
-
-	check_guarded_expression free_vars {alt_nodes,alt_guard,alt_expr,alt_ident,alt_position}
-			let_vars_list rev_guarded_exprs e_input=:{ei_expr_level,ei_mod_index} e_state e_info cs
-		# (let_binds, let_vars_list, ei_expr_level, free_vars, e_state, e_info, cs) = check_sequential_lets free_vars alt_nodes let_vars_list
-		  		{ e_input & ei_expr_level = inc ei_expr_level } e_state e_info cs
-		  e_input = { e_input & ei_expr_level = ei_expr_level }
-		  cs = pushErrorAdmin2 "guard" alt_position cs
-	  	  (guard, free_vars, e_state, e_info, cs) = checkExpression free_vars alt_guard e_input e_state e_info cs
-		  cs = popErrorAdmin cs
-		  (expr, free_vars, e_state, e_info, cs) = check_opt_guarded_alts free_vars alt_expr e_input e_state e_info cs
-	  	= (let_vars_list, [(let_binds, guard, expr, alt_ident) : rev_guarded_exprs], ei_expr_level, free_vars, e_state, e_info,  cs )
-
-	check_unguarded_expression :: [FreeVar] ExprWithLocalDefs ExpressionInput *ExpressionState *ExpressionInfo *CheckState -> *(!Expression,![FreeVar],!*ExpressionState,!*ExpressionInfo,!*CheckState);
-	check_unguarded_expression free_vars {ewl_nodes,ewl_expr,ewl_locals,ewl_position} e_input=:{ei_expr_level,ei_mod_index} e_state e_info cs
-		# this_expr_level = inc ei_expr_level
-		  (loc_defs, (var_env, array_patterns), e_state, e_info, cs)
-		 		= checkLhssOfLocalDefs this_expr_level ei_mod_index ewl_locals e_state e_info cs
-		  (binds, let_vars_list, rhs_expr_level, free_vars, e_state, e_info, cs) = check_sequential_lets free_vars ewl_nodes [] { e_input & ei_expr_level = this_expr_level } e_state e_info cs
-		  cs = pushErrorAdmin2 "" ewl_position cs
-	  	  (expr, free_vars, e_state, e_info, cs) = checkExpression free_vars ewl_expr { e_input & ei_expr_level = rhs_expr_level } e_state e_info cs
-		  cs = popErrorAdmin cs
-		  (expr, free_vars, e_state, e_info, cs)
-				= addArraySelections array_patterns expr free_vars e_input e_state e_info cs
-		  cs = { cs & cs_symbol_table = remove_seq_let_vars rhs_expr_level let_vars_list cs.cs_symbol_table }
-		  (_, seq_let_expr, es_expr_heap) = build_sequential_lets binds expr ewl_position e_state.es_expr_heap
-	  	  (expr, free_vars, e_state, e_info, cs)
-				= checkRhssAndTransformLocalDefs free_vars loc_defs seq_let_expr e_input { e_state & es_expr_heap = es_expr_heap} e_info cs
-	  	  (es_fun_defs, e_info, heaps, cs)
-	  	  		= checkLocalFunctions ei_mod_index rhs_expr_level ewl_locals e_state.es_fun_defs e_info 
-	  	  		{ hp_var_heap = e_state.es_var_heap, hp_expression_heap = e_state.es_expr_heap, hp_type_heaps = e_state.es_type_heaps } cs
-		  (es_fun_defs, cs_symbol_table) = removeLocalsFromSymbolTable this_expr_level var_env ewl_locals es_fun_defs cs.cs_symbol_table
-	  	= (expr, free_vars, {e_state & es_fun_defs = es_fun_defs, es_var_heap = heaps.hp_var_heap,
-	  			es_expr_heap = heaps.hp_expression_heap, es_type_heaps = heaps.hp_type_heaps }, e_info, { cs & cs_symbol_table = cs_symbol_table} )
-	
-	remove_seq_let_vars level [] symbol_table
-		= symbol_table
-	remove_seq_let_vars level [let_vars : let_vars_list] symbol_table
-		= remove_seq_let_vars (dec level) let_vars_list (removeLocalIdentsFromSymbolTable level let_vars symbol_table)
-	
-	check_sequential_lets :: [FreeVar] [NodeDefWithLocals] u:[[Ident]] !ExpressionInput *ExpressionState *ExpressionInfo *CheckState 
-						-> *(![.([LetBind],![LetBind])],!u:[[Ident]],!Int,![FreeVar],!*ExpressionState,!*ExpressionInfo,!*CheckState);
-	check_sequential_lets free_vars [seq_let:seq_lets] let_vars_list e_input=:{ei_expr_level,ei_mod_index} e_state e_info cs
-		# ei_expr_level
-				= inc ei_expr_level
-		  e_input
-		  		= { e_input & ei_expr_level = ei_expr_level }
-		  (src_expr, pattern_expr, (let_vars, array_patterns), free_vars, e_state, e_info, cs)
-		  		= check_sequential_let free_vars seq_let e_input e_state e_info cs
-	      (binds, loc_envs, max_expr_level, free_vars, e_state, e_info, cs)
-	      		= check_sequential_lets free_vars seq_lets [let_vars : let_vars_list] e_input e_state e_info cs
-		  (let_binds, es_var_heap, es_expr_heap, e_info, cs)
-				= transfromPatternIntoBind ei_mod_index ei_expr_level pattern_expr src_expr seq_let.ndwl_position
-						e_state.es_var_heap e_state.es_expr_heap e_info cs
-		  e_state
-		  		= { e_state & es_var_heap = es_var_heap, es_expr_heap = es_expr_heap }
-		  (strict_array_pattern_binds, lazy_array_pattern_binds, free_vars, e_state, e_info, cs)
-				= foldSt (buildSelections e_input) array_patterns ([], [], free_vars, e_state, e_info, cs)
-		  all_binds
-		  		= [if seq_let.ndwl_strict (s, l) ([],let_binds), (strict_array_pattern_binds, lazy_array_pattern_binds) : binds]
-		    with (l,s) = splitAt ((length let_binds)-1) let_binds
-	    = (all_binds, loc_envs, max_expr_level, free_vars, e_state, e_info, cs)
-	check_sequential_lets free_vars [] let_vars_list e_input=:{ei_expr_level} e_state e_info cs
-		= ([], let_vars_list, ei_expr_level, free_vars, e_state, e_info, cs)
-
-	check_sequential_let :: [FreeVar] NodeDefWithLocals ExpressionInput *ExpressionState *ExpressionInfo *CheckState -> *(!Expression,!AuxiliaryPattern,!(![Ident],![ArrayPattern]),![FreeVar],!*ExpressionState,!*ExpressionInfo,!*CheckState);
-	check_sequential_let free_vars {ndwl_def={bind_src,bind_dst},ndwl_locals, ndwl_position} e_input=:{ei_expr_level,ei_mod_index} e_state e_info cs
-		# cs = pushErrorAdmin (newPosition {id_name="node definition", id_info=nilPtr} ndwl_position) cs
-		  (loc_defs, (loc_env, loc_array_patterns), e_state, e_info, cs) = checkLhssOfLocalDefs ei_expr_level ei_mod_index ndwl_locals e_state e_info cs
-		  (src_expr, free_vars, e_state, e_info, cs) = checkExpression free_vars bind_src e_input e_state e_info cs
-		  (src_expr, free_vars, e_state, e_info, cs)
-				= addArraySelections loc_array_patterns src_expr free_vars e_input e_state e_info cs
-		  (src_expr, free_vars, e_state, e_info, cs) = checkRhssAndTransformLocalDefs free_vars loc_defs src_expr e_input e_state e_info cs
-		  (es_fun_defs, e_info, {hp_var_heap,hp_expression_heap,hp_type_heaps}, cs)
-				= checkLocalFunctions ei_mod_index ei_expr_level ndwl_locals e_state.es_fun_defs e_info
-	  				{ hp_var_heap = e_state.es_var_heap, hp_expression_heap = e_state.es_expr_heap, hp_type_heaps = e_state.es_type_heaps } cs
-	  	  (es_fun_defs, cs_symbol_table) = removeLocalsFromSymbolTable ei_expr_level loc_env ndwl_locals es_fun_defs cs.cs_symbol_table
-		  (pattern, accus, {ps_fun_defs,ps_var_heap}, e_info, cs)
-				= checkPattern bind_dst No { pi_def_level = ei_expr_level, pi_mod_index = ei_mod_index, pi_is_node_pattern = True } ([], []) 
-					{ps_var_heap = hp_var_heap, ps_fun_defs = es_fun_defs } e_info { cs & cs_symbol_table = cs_symbol_table }
-		  e_state = { e_state & es_var_heap = ps_var_heap, es_expr_heap = hp_expression_heap, es_type_heaps = hp_type_heaps, es_fun_defs = ps_fun_defs }
-		= (src_expr, pattern, accus, free_vars, e_state, e_info, popErrorAdmin cs)
-	
-	build_sequential_lets :: ![(![LetBind],![LetBind])] !Expression !Position !*ExpressionHeap -> (!Position, !Expression, !*ExpressionHeap)
-	build_sequential_lets [] expr let_expr_position expr_heap
-		= (let_expr_position, expr, expr_heap)
-	build_sequential_lets [(strict_binds, lazy_binds) : seq_lets] expr let_expr_position expr_heap
-		# (let_expr_position, let_expr, expr_heap) = build_sequential_lets seq_lets expr let_expr_position expr_heap
-	  	  (let_expr, expr_heap) = buildLetExpression strict_binds lazy_binds let_expr let_expr_position expr_heap
-		= (if (isEmpty strict_binds && isEmpty lazy_binds) let_expr_position NoPos, let_expr, expr_heap)
-
-newVarId name = { id_name = name, id_info = nilPtr }
-
-determinePatternVariable (Yes bind) var_heap
-	= (bind, var_heap)
-determinePatternVariable No var_heap
-	# (new_info_ptr, var_heap) = newPtr VI_Empty var_heap
-	= ({ bind_src = newVarId "_x", bind_dst = new_info_ptr }, var_heap)
-
-convertSubPatterns :: [AuxiliaryPattern] Expression Position *(Heap VarInfo) *(Heap ExprInfo) u:[Ptr ExprInfo] *CheckState -> *(!.[FreeVar],!Expression,!Position,!*Heap VarInfo,!*Heap ExprInfo,!u:[Ptr ExprInfo],!*CheckState);
-convertSubPatterns [] result_expr pattern_position var_store expr_heap opt_dynamics cs
-	= ([], result_expr, pattern_position, var_store, expr_heap, opt_dynamics, cs)
-convertSubPatterns [pattern : patterns] result_expr pattern_position var_store expr_heap opt_dynamics cs
-	# (var_args, result_expr, pattern_position, var_store, expr_heap, opt_dynamics, cs) 
-			= convertSubPatterns patterns result_expr pattern_position var_store expr_heap opt_dynamics cs
-	  (var_arg, result_expr, pattern_position, var_store, expr_heap, opt_dynamics, cs)
-	  		= convertSubPattern pattern result_expr pattern_position var_store expr_heap opt_dynamics cs
-	= ([var_arg : var_args], result_expr, pattern_position, var_store, expr_heap, opt_dynamics, cs)
-
-convertSubPattern :: AuxiliaryPattern Expression Position *(Heap VarInfo) *(Heap ExprInfo) u:[Ptr ExprInfo] *CheckState -> *(!FreeVar,!Expression,!Position,!*Heap VarInfo,!*Heap ExprInfo,!u:[Ptr ExprInfo],!*CheckState);
-convertSubPattern (AP_Variable name var_info (Yes {bind_src,bind_dst})) result_expr pattern_position var_store expr_heap opt_dynamics cs
-	# (var_expr_ptr, expr_heap) = newPtr EI_Empty expr_heap
-	  bound_var = { var_name = bind_src, var_info_ptr = bind_dst, var_expr_ptr = var_expr_ptr }
-	  free_var = { fv_name = bind_src, fv_info_ptr = bind_dst, fv_def_level = NotALevel, fv_count = 0 }
-	  (let_expr, expr_heap)	= buildLetExpression [] [{lb_src = Var bound_var,
-	  			lb_dst = { fv_name = name, fv_info_ptr = var_info, fv_def_level = NotALevel, fv_count = 0 },
-	  			lb_position = NoPos }] result_expr NoPos expr_heap
-	= (free_var, let_expr, pattern_position, var_store, expr_heap, opt_dynamics, cs)
-convertSubPattern (AP_Variable name var_info No) result_expr pattern_position var_store expr_heap opt_dynamics cs
-	= ({ fv_name = name, fv_info_ptr = var_info, fv_def_level = NotALevel, fv_count = 0 }, result_expr, pattern_position, 
-		var_store, expr_heap, opt_dynamics, cs)
-convertSubPattern (AP_Algebraic cons_symbol type_index args opt_var) result_expr pattern_position
-					var_store expr_heap opt_dynamics cs
-	# (var_args, result_expr, pattern_position, var_store, expr_heap, opt_dynamics, cs)
-			= convertSubPatterns args result_expr pattern_position var_store expr_heap opt_dynamics cs
-	  type_symbol = { glob_module = cons_symbol.glob_module, glob_object = type_index }
-	  alg_pattern = { ap_symbol = cons_symbol, ap_vars = var_args, ap_expr = result_expr, ap_position = pattern_position }
-	  case_guards = AlgebraicPatterns type_symbol [alg_pattern]
-	  ({bind_src,bind_dst}, var_store) = determinePatternVariable opt_var var_store
-	  (var_expr_ptr, expr_heap) = newPtr EI_Empty expr_heap
-	  (case_expr_ptr, expr_heap) = newPtr EI_Empty expr_heap
-	= ({ fv_name = bind_src, fv_info_ptr = bind_dst, fv_def_level = NotALevel, fv_count = 0 },
-		Case { case_expr = Var { var_name = bind_src, var_info_ptr = bind_dst, var_expr_ptr = var_expr_ptr },
-				case_guards = case_guards, case_default = No, case_ident = No, case_info_ptr = case_expr_ptr,
-				case_default_pos = NoPos },
-		NoPos, var_store, expr_heap, opt_dynamics, cs)
-convertSubPattern (AP_Basic basic_val opt_var) result_expr pattern_position var_store expr_heap opt_dynamics cs
-	# (basic_type, cs) = typeOfBasicValue basic_val cs
-	  case_guards = BasicPatterns basic_type [{ bp_value = basic_val, bp_expr = result_expr, bp_position = pattern_position }]
-  	  ({bind_src,bind_dst}, var_store) = determinePatternVariable opt_var var_store
-	  (var_expr_ptr, expr_heap) = newPtr EI_Empty expr_heap
-	  (case_expr_ptr, expr_heap) = newPtr EI_Empty expr_heap
-	= ({ fv_name = bind_src, fv_info_ptr = bind_dst, fv_def_level = NotALevel, fv_count = 0 },
-		Case { case_expr = Var { var_name = bind_src, var_info_ptr = bind_dst, var_expr_ptr = var_expr_ptr },
-			  case_guards = case_guards, case_default = No, case_ident = No, case_info_ptr = case_expr_ptr,
-			  case_default_pos = NoPos},
-		NoPos, var_store, expr_heap, opt_dynamics, cs)
-convertSubPattern (AP_Dynamic pattern type opt_var) result_expr pattern_position var_store expr_heap opt_dynamics cs
-	# (var_arg, result_expr, pattern_position, var_store, expr_heap, opt_dynamics, cs)
-			= convertSubPattern pattern result_expr pattern_position var_store expr_heap opt_dynamics cs
- 	  ({bind_src,bind_dst}, var_store) = determinePatternVariable opt_var var_store
-	  (var_expr_ptr, expr_heap) = newPtr EI_Empty expr_heap
-	  (type_case_info_ptr, expr_heap) = newPtr EI_Empty expr_heap
-	  (dynamic_info_ptr, expr_heap) = newPtr (EI_DynamicType type opt_dynamics) expr_heap
- 	  type_case_patterns = [{ dp_var = var_arg, dp_type = dynamic_info_ptr, dp_rhs = result_expr, dp_type_patterns_vars = [],
- 	  						dp_type_code = TCE_Empty, dp_position = pattern_position }]
-	= ({ fv_name = bind_src, fv_info_ptr = bind_dst, fv_def_level = NotALevel, fv_count = 0 },
-		buildTypeCase (Var { var_name = bind_src, var_info_ptr = bind_dst, var_expr_ptr = var_expr_ptr }) 
-							type_case_patterns No type_case_info_ptr,
-		NoPos, var_store, expr_heap, [dynamic_info_ptr], cs)
-convertSubPattern (AP_WildCard opt_var) result_expr pattern_position var_store expr_heap opt_dynamics cs
- 	# ({bind_src,bind_dst}, var_store) = determinePatternVariable opt_var var_store
-	= ({ fv_name = bind_src, fv_info_ptr = bind_dst, fv_def_level = NotALevel, fv_count = 0  }, result_expr, pattern_position,
-		var_store, expr_heap, opt_dynamics, cs)
-convertSubPattern (AP_Empty _) result_expr pattern_position var_store expr_heap opt_dynamics cs
-	= convertSubPattern (AP_WildCard No) EE pattern_position var_store expr_heap opt_dynamics cs
-
-typeOfBasicValue :: !BasicValue !*CheckState -> (!BasicType, !*CheckState)
-typeOfBasicValue (BVI _) cs = (BT_Int, cs)
-typeOfBasicValue (BVC _) cs = (BT_Char, cs)
-typeOfBasicValue (BVB _) cs = (BT_Bool, cs)
-typeOfBasicValue (BVR _) cs = (BT_Real, cs)
-typeOfBasicValue (BVS _) cs
-	# ({glob_module,glob_object={ds_ident,ds_index,ds_arity}}, cs) = getPredefinedGlobalSymbol PD_StringType PD_PredefinedModule STE_Type 0 cs
-	= (BT_String (TA (MakeTypeSymbIdent { glob_object = ds_index, glob_module = glob_module } ds_ident ds_arity) []), cs)
-
-
-addArraySelections [] rhs_expr free_vars e_input e_state e_info cs
-	= (rhs_expr, free_vars, e_state, e_info, cs)
-addArraySelections array_patterns rhs_expr free_vars e_input e_state e_info cs
-	# (let_strict_binds, let_lazy_binds, free_vars, e_state, e_info, cs)
-			= foldSt (buildSelections e_input) array_patterns ([], [], free_vars, e_state, e_info, cs)
-	  (let_expr_ptr, es_expr_heap)
-	  		= newPtr EI_Empty e_state.es_expr_heap
-	= ( Let {let_strict_binds = let_strict_binds, let_lazy_binds = let_lazy_binds,
-				let_expr = rhs_expr, let_info_ptr = let_expr_ptr, let_expr_position = NoPos }
-	  , free_vars
-	  , { e_state & es_expr_heap = es_expr_heap}
-	  , e_info
-	  , cs
-	  )
-
-buildSelections e_input {ap_opt_var, ap_array_var, ap_selections}
-					(strict_binds, lazy_binds, free_vars, e_state, e_info, cs)
-	# (ap_array_var, [last_array_selection:lazy_binds], free_vars, e_state, e_info, cs)
-			= foldSt (build_sc e_input) (reverse ap_selections) // reverse to make cycle-in-spine behaviour compatible to Clean 1.3
-						(ap_array_var, lazy_binds, free_vars, e_state, e_info, cs)
-	  (lazy_binds, e_state)
-	  		= case ap_opt_var of
-	  			Yes { bind_src = opt_var_ident, bind_dst = opt_var_var_info_ptr }
-					# (bound_array_var, es_expr_heap) = allocate_bound_var ap_array_var e_state.es_expr_heap
-					  free_var = { fv_name = opt_var_ident, fv_info_ptr = opt_var_var_info_ptr, fv_def_level = NotALevel,
-					  				fv_count = 0 }
-	  				-> ([{ lb_dst = free_var, lb_src = Var bound_array_var, lb_position = NoPos }: lazy_binds],
-	  					{ e_state & es_expr_heap = es_expr_heap })
-	  			no	-> (lazy_binds, e_state)
-	= ([last_array_selection:strict_binds], lazy_binds, free_vars, e_state, e_info, cs)
-  where
-	build_sc e_input {bind_dst=parsed_index_exprs, bind_src=array_element_var} (ap_array_var, binds, free_vars, e_state, e_info, cs)
-		# (var_for_uselect_result, es_var_heap)
-				= allocate_free_var { id_name = "_x", id_info = nilPtr } e_state.es_var_heap
-		  (new_array_var, es_var_heap)
-		  		= allocate_free_var ap_array_var.fv_name es_var_heap
-		  (bound_array_var, es_expr_heap)
-		  		= allocate_bound_var ap_array_var e_state.es_expr_heap
-		  (bound_var_for_uselect_result, es_expr_heap)
-		  		= allocate_bound_var var_for_uselect_result es_expr_heap
-		  dimension
-		  		= length parsed_index_exprs
-		  (new_expr_ptrs, es_expr_heap)
-		  		= mapSt newPtr (repeatn dimension EI_Empty) es_expr_heap
-		  (tuple_cons, cs)
-		  		= getPredefinedGlobalSymbol (GetTupleConsIndex 2) PD_PredefinedModule STE_Constructor 2 cs
-		  (glob_select_symb, opt_tuple_type, cs)
-		  		= case dimension of
-		  			1	# (unq_select_symb, cs) = getPredefinedGlobalSymbol PD_UnqArraySelectFun PD_StdArray STE_Member 2 cs
-		  				-> (unq_select_symb, No, cs)
-		  			_	# (select_symb, cs) = getPredefinedGlobalSymbol PD_ArraySelectFun PD_StdArray STE_Member 2 cs
-						  (tuple_type, cs) = getPredefinedGlobalSymbol (GetTupleTypeIndex 2) PD_PredefinedModule STE_Type 2 cs
-		  				-> (select_symb, Yes tuple_type, cs)
-		  e_state
-		  		= { e_state & es_var_heap = es_var_heap, es_expr_heap = es_expr_heap }
-		  (index_exprs, (free_vars, e_state, e_info, cs))
-		  		= mapSt (check_index_expr e_input) parsed_index_exprs (free_vars, e_state, e_info, cs)
-		  selections
-		  		= [ ArraySelection glob_select_symb new_expr_ptr index_expr \\ new_expr_ptr<-new_expr_ptrs & index_expr<-index_exprs ]
-		= (	new_array_var
-		  ,	[ {lb_dst = var_for_uselect_result, lb_src = Selection opt_tuple_type (Var bound_array_var) selections, lb_position = NoPos }
-		    , {lb_dst = new_array_var, lb_src = TupleSelect tuple_cons.glob_object 1 (Var bound_var_for_uselect_result), lb_position = NoPos }
-		    , {lb_dst = array_element_var, lb_src = TupleSelect tuple_cons.glob_object 0 (Var bound_var_for_uselect_result), lb_position = NoPos }
-		  	: binds
-			]
-		  , free_vars
-		  , e_state
-		  , e_info 
-		  , cs
-		  )
-
-	check_index_expr e_input parsed_index_expr (free_vars, e_state, e_info, cs)
-		# (index_expr, free_vars, e_state, e_info, cs) = checkExpression free_vars parsed_index_expr e_input e_state e_info cs
-		= (index_expr, (free_vars, e_state, e_info, cs))
-		
-allocate_free_var ident var_heap
-	# (new_var_info_ptr, var_heap) = newPtr VI_Empty var_heap
-	= ({ fv_def_level = NotALevel, fv_name = ident, fv_info_ptr = new_var_info_ptr,	fv_count = 0 }, var_heap)
-
-checkFunctionBodies (ParsedBody [{pb_args,pb_rhs={rhs_alts,rhs_locals}, pb_position} : bodies]) e_input=:{ei_expr_level,ei_mod_index}
-		e_state=:{es_var_heap, es_fun_defs} e_info cs
-	# (aux_patterns, (var_env, array_patterns), {ps_var_heap, ps_fun_defs}, e_info, cs)
-			= check_patterns pb_args {pi_def_level = ei_expr_level, pi_mod_index = ei_mod_index, pi_is_node_pattern = False} ([], [])
-							{ps_var_heap = es_var_heap, ps_fun_defs = es_fun_defs} e_info cs 
-	  (rhs_expr, free_vars, e_state, e_info, cs)
-	  		= checkRhs [] rhs_alts rhs_locals e_input { e_state & es_var_heap = ps_var_heap, es_fun_defs = ps_fun_defs } e_info cs
-	  (dynamics_in_rhs, e_state)
-	  		= e_state!es_dynamics
-	  (expr_with_array_selections, free_vars, e_state=:{es_var_heap}, e_info, cs)
-			= addArraySelections array_patterns rhs_expr free_vars e_input e_state e_info cs
-	  cs_symbol_table = removeLocalIdentsFromSymbolTable ei_expr_level var_env cs.cs_symbol_table
-	  (cb_args, es_var_heap) = mapSt determine_function_arg aux_patterns es_var_heap
-	  (rhss, free_vars, e_state=:{es_dynamics,es_expr_heap,es_var_heap}, e_info, cs)
-	  		= check_function_bodies free_vars cb_args bodies e_input { e_state & es_dynamics = [], es_var_heap = es_var_heap } e_info
-	  								{ cs & cs_symbol_table = cs_symbol_table }
-	  (rhs, position, es_var_heap, es_expr_heap, dynamics_in_patterns, cs)
-	  		= transform_patterns_into_cases aux_patterns cb_args expr_with_array_selections pb_position es_var_heap es_expr_heap
-	  										dynamics_in_rhs cs
-	= (CheckedBody { cb_args = cb_args, cb_rhs = [{ ca_rhs = rhs, ca_position = position } : rhss] }, free_vars,
-		{ e_state & es_var_heap = es_var_heap, es_expr_heap = es_expr_heap, es_dynamics = dynamics_in_patterns ++ es_dynamics }, e_info, cs)
-where
-	check_patterns [pattern : patterns] p_input accus var_store e_info cs
-		# (aux_pat, accus, var_store, e_info, cs) = checkPattern pattern No p_input accus var_store e_info cs
-		  (aux_pats, accus, var_store, e_info, cs) = check_patterns patterns p_input accus var_store e_info cs
-		= ([aux_pat : aux_pats], accus, var_store, e_info, cs)
-	check_patterns [] p_input accus var_store e_info cs
-		= ([], accus, var_store, e_info, cs)
-
-	determine_function_arg (AP_Variable name var_info (Yes {bind_src, bind_dst})) var_store
-		= ({ fv_name = bind_src, fv_info_ptr = bind_dst, fv_def_level = NotALevel, fv_count = 0 }, var_store)
-	determine_function_arg (AP_Variable name var_info No) var_store
-		= ({ fv_name = name, fv_info_ptr = var_info, fv_def_level = NotALevel, fv_count = 0 }, var_store)
-	determine_function_arg (AP_Algebraic _ _ _ opt_var) var_store
-		# ({bind_src,bind_dst}, var_store) = determinePatternVariable opt_var var_store
-		= ({ fv_name = bind_src, fv_info_ptr = bind_dst, fv_def_level = NotALevel, fv_count = 0 }, var_store)
-	determine_function_arg (AP_Basic _ opt_var) var_store
-		# ({bind_src,bind_dst}, var_store) = determinePatternVariable opt_var var_store
-		= ({ fv_name = bind_src, fv_info_ptr = bind_dst, fv_def_level = NotALevel, fv_count = 0 }, var_store)
-	determine_function_arg (AP_Dynamic _ _ opt_var) var_store
-		# ({bind_src,bind_dst}, var_store) = determinePatternVariable opt_var var_store
-		= ({ fv_name = bind_src, fv_info_ptr = bind_dst, fv_def_level = NotALevel, fv_count = 0 }, var_store)
-	determine_function_arg _ var_store
-		# ({bind_src,bind_dst}, var_store) = determinePatternVariable No var_store
-		= ({ fv_name = bind_src, fv_info_ptr = bind_dst, fv_def_level = NotALevel, fv_count = 0 }, var_store)
-	
-	check_function_bodies free_vars fun_args [{pb_args,pb_rhs={rhs_alts,rhs_locals},pb_position} : bodies]
-							e_input=:{ei_expr_level,ei_mod_index} e_state=:{es_var_heap,es_fun_defs} e_info cs
-		# (aux_patterns, (var_env, array_patterns), {ps_var_heap, ps_fun_defs}, e_info, cs)
-				= check_patterns pb_args { pi_def_level = ei_expr_level, pi_mod_index = ei_mod_index, pi_is_node_pattern = False } ([], [])
-					{ps_var_heap = es_var_heap, ps_fun_defs = es_fun_defs} e_info cs
-		  e_state = { e_state & es_var_heap = ps_var_heap, es_fun_defs = ps_fun_defs}
-		  (rhs_expr, free_vars, e_state, e_info, cs) = checkRhs free_vars rhs_alts rhs_locals e_input e_state e_info cs
-		  (rhs_expr, free_vars, e_state=:{es_dynamics=dynamics_in_rhs}, e_info, cs)
-				= addArraySelections array_patterns rhs_expr free_vars e_input e_state e_info cs
-	 	  cs_symbol_table = removeLocalIdentsFromSymbolTable ei_expr_level var_env cs.cs_symbol_table
-		  (rhs_exprs, free_vars, e_state=:{es_dynamics,es_expr_heap,es_var_heap}, e_info, cs)
-		  		= check_function_bodies free_vars fun_args bodies e_input { e_state & es_dynamics = [] } e_info { cs & cs_symbol_table = cs_symbol_table }
-		  (rhs_expr, position, es_var_heap, es_expr_heap, dynamics_in_patterns, cs)
-		  		= transform_patterns_into_cases aux_patterns fun_args rhs_expr pb_position
-		  										 es_var_heap es_expr_heap dynamics_in_rhs cs
-		= ([{ ca_rhs = rhs_expr, ca_position = position } : rhs_exprs], free_vars,
-			{ e_state & es_var_heap = es_var_heap, es_expr_heap = es_expr_heap,
-			es_dynamics = dynamics_in_patterns ++ es_dynamics }, e_info, cs)
-	check_function_bodies free_vars fun_args [] e_input e_state e_info cs
-		= ([], free_vars, e_state, e_info, cs) 
-		
-	transform_patterns_into_cases [pattern : patterns] [fun_arg : fun_args] result_expr pattern_position
-									var_store expr_heap opt_dynamics cs
-		# (patterns_expr, pattern_position, var_store, expr_heap, opt_dynamics, cs)
-				= transform_succeeding_patterns_into_cases patterns fun_args result_expr pattern_position
-															var_store expr_heap opt_dynamics cs
-		= transform_pattern_into_cases pattern fun_arg patterns_expr pattern_position var_store expr_heap opt_dynamics cs
-	where
-		transform_succeeding_patterns_into_cases [] _ result_expr pattern_position var_store expr_heap opt_dynamics cs
-			= (result_expr, pattern_position, var_store, expr_heap, opt_dynamics, cs)
-		transform_succeeding_patterns_into_cases [pattern : patterns] [fun_arg : fun_args] result_expr pattern_position
-												var_store expr_heap opt_dynamics cs
-			# (patterns_expr, pattern_position, var_store, expr_heap, opt_dynamics, cs)
-				= transform_succeeding_patterns_into_cases patterns fun_args result_expr pattern_position
-															var_store expr_heap opt_dynamics cs
-			= transform_pattern_into_cases pattern fun_arg patterns_expr pattern_position var_store expr_heap opt_dynamics cs
-
-	transform_patterns_into_cases [] _ result_expr pattern_position var_store expr_heap opt_dynamics cs
-		= (result_expr, pattern_position, var_store, expr_heap, opt_dynamics, cs)
-
-	transform_pattern_into_cases :: !AuxiliaryPattern !FreeVar !Expression !Position !*VarHeap !*ExpressionHeap ![DynamicPtr] !*CheckState
-		-> (!Expression, !Position, !*VarHeap, !*ExpressionHeap, ![DynamicPtr], !*CheckState)
-	transform_pattern_into_cases (AP_Variable name var_info opt_var) fun_arg=:{fv_info_ptr,fv_name} result_expr pattern_position
-									var_store expr_heap opt_dynamics cs
-		= case opt_var of
-			Yes {bind_src, bind_dst}
-				| bind_dst == fv_info_ptr
-					# (var_expr_ptr, expr_heap) = newPtr EI_Empty expr_heap
-					  (let_expr_ptr, expr_heap) = newPtr EI_Empty expr_heap
-					-> (Let { let_strict_binds = [], let_lazy_binds= [
-								{ lb_src = Var { var_name = fv_name, var_info_ptr = fv_info_ptr, var_expr_ptr = var_expr_ptr },
-									lb_dst = { fv_name = name, fv_info_ptr = var_info, fv_def_level = NotALevel, fv_count = 0 },
-									lb_position = NoPos }],
-							  let_expr = result_expr, let_info_ptr = let_expr_ptr, let_expr_position = NoPos }, 
-						pattern_position, var_store, expr_heap, opt_dynamics, cs)
-					# (var_expr_ptr1, expr_heap) = newPtr EI_Empty expr_heap
-					  (var_expr_ptr2, expr_heap) = newPtr EI_Empty expr_heap
-					  (let_expr_ptr, expr_heap) = newPtr EI_Empty expr_heap
-					-> (Let { let_strict_binds = [], let_lazy_binds= [
-								{ lb_src = Var { var_name = fv_name, var_info_ptr = fv_info_ptr, var_expr_ptr = var_expr_ptr1 },
-									lb_dst = { fv_name = name, fv_info_ptr = var_info, fv_def_level = NotALevel, fv_count = 0 },
-									lb_position = NoPos },
-								{ lb_src = Var { var_name = fv_name, var_info_ptr = fv_info_ptr, var_expr_ptr = var_expr_ptr2 },
-									lb_dst = { fv_name = bind_src, fv_info_ptr = bind_dst, fv_def_level = NotALevel, fv_count = 0 },
-									lb_position = NoPos }],
-							  let_expr = result_expr, let_info_ptr = let_expr_ptr, let_expr_position = NoPos }, 
-						pattern_position, var_store, expr_heap, opt_dynamics, cs)
-			No
-				| var_info == fv_info_ptr
-					-> (result_expr, pattern_position, var_store, expr_heap, opt_dynamics, cs)
-					# (var_expr_ptr, expr_heap) = newPtr EI_Empty expr_heap
-					  (let_expr_ptr, expr_heap) = newPtr EI_Empty expr_heap
-					-> (Let { let_strict_binds = [], let_lazy_binds=
-									[{ lb_src = Var { var_name = fv_name, var_info_ptr = fv_info_ptr, var_expr_ptr = var_expr_ptr },
-										 lb_dst = { fv_name = name, fv_info_ptr = var_info, fv_def_level = NotALevel, fv_count = 0 },
-										 lb_position = NoPos }],
-							  let_expr = result_expr, let_info_ptr = let_expr_ptr, let_expr_position = NoPos },
-						pattern_position, var_store, expr_heap, opt_dynamics, cs)
-
-	transform_pattern_into_cases (AP_Algebraic cons_symbol type_index args opt_var) fun_arg result_expr pattern_position
-									var_store expr_heap opt_dynamics cs
-		# (var_args, result_expr, pattern_position, var_store, expr_heap, opt_dynamics, cs)
-				= convertSubPatterns args result_expr pattern_position var_store expr_heap opt_dynamics cs
-		  type_symbol = {glob_module = cons_symbol.glob_module, glob_object = type_index}
-	  	  (act_var, result_expr, expr_heap) = transform_pattern_variable fun_arg opt_var result_expr expr_heap
-		  alg_pattern = { ap_symbol = cons_symbol, ap_vars = var_args, ap_expr = result_expr, ap_position = pattern_position }
-	  	  case_guards = AlgebraicPatterns type_symbol [alg_pattern]
-		  (case_expr_ptr, expr_heap) = newPtr EI_Empty expr_heap
-		= (Case { case_expr = act_var, case_guards = case_guards, case_default = No, case_ident = No,
-				case_info_ptr = case_expr_ptr, case_default_pos = NoPos },
-				NoPos, var_store, expr_heap, opt_dynamics, cs)	
-	transform_pattern_into_cases (AP_Basic basic_val opt_var) fun_arg result_expr pattern_position var_store expr_heap opt_dynamics cs
-		# (basic_type, cs) = typeOfBasicValue basic_val cs
-	  	  (act_var, result_expr, expr_heap) = transform_pattern_variable fun_arg opt_var result_expr expr_heap
-		  case_guards = BasicPatterns basic_type [{ bp_value = basic_val, bp_expr = result_expr, bp_position = pattern_position }]
-		  (case_expr_ptr, expr_heap) = newPtr EI_Empty expr_heap
-		= (Case { case_expr = act_var, case_guards = case_guards, case_default = No, case_ident = No,
-					case_info_ptr = case_expr_ptr, case_default_pos = NoPos },
-			NoPos, var_store, expr_heap, opt_dynamics, cs)	
-	transform_pattern_into_cases (AP_Dynamic pattern type opt_var) fun_arg result_expr pattern_position var_store expr_heap opt_dynamics cs
-		# (var_arg, result_expr, pattern_position, var_store, expr_heap, opt_dynamics, cs)
-				= convertSubPattern pattern result_expr pattern_position var_store expr_heap opt_dynamics cs
-		  (type_case_info_ptr, expr_heap) = newPtr EI_Empty expr_heap
-		  (dynamic_info_ptr, expr_heap) = newPtr (EI_DynamicType type opt_dynamics) expr_heap
-	  	  (act_var, result_expr, expr_heap) = transform_pattern_variable fun_arg opt_var result_expr expr_heap
-	  	  type_case_patterns = [{ dp_var = var_arg, dp_type	= dynamic_info_ptr,	dp_rhs = result_expr, dp_type_patterns_vars = [],
-	  	  							dp_type_code = TCE_Empty, dp_position = pattern_position }]
-		= (buildTypeCase act_var type_case_patterns No type_case_info_ptr, NoPos, var_store, expr_heap, [dynamic_info_ptr], cs)	
-	transform_pattern_into_cases (AP_WildCard _) fun_arg result_expr pattern_position var_store expr_heap opt_dynamics cs
-		= (result_expr, pattern_position, var_store, expr_heap, opt_dynamics, cs)	
-	transform_pattern_into_cases (AP_Empty name) fun_arg result_expr pattern_position var_store expr_heap opt_dynamics cs
-		= (result_expr, pattern_position, var_store, expr_heap, opt_dynamics, cs)
-
-	transform_pattern_variable :: !FreeVar !(Optional !(Bind Ident VarInfoPtr)) !Expression !*ExpressionHeap
-		-> (!Expression, !Expression, !*ExpressionHeap)
-	transform_pattern_variable {fv_info_ptr,fv_name} (Yes {bind_src,bind_dst}) result_expr expr_heap
-		| bind_dst == fv_info_ptr
-			# (var_expr_ptr, expr_heap) = newPtr EI_Empty expr_heap
-			= (Var { var_name = fv_name, var_info_ptr = fv_info_ptr, var_expr_ptr = var_expr_ptr }, result_expr, expr_heap)
-			# (var_expr_ptr1, expr_heap) = newPtr EI_Empty expr_heap
-			  (var_expr_ptr2, expr_heap) = newPtr EI_Empty expr_heap
-			  (let_expr_ptr, expr_heap) = newPtr EI_Empty expr_heap
-			= (Var { var_name = fv_name, var_info_ptr = fv_info_ptr, var_expr_ptr = var_expr_ptr1 },
-						Let { let_strict_binds = [], let_lazy_binds =
-						 		[{ lb_src = Var { var_name = fv_name, var_info_ptr = fv_info_ptr, var_expr_ptr = var_expr_ptr2 },
-									lb_dst = { fv_name = bind_src, fv_info_ptr = bind_dst, fv_def_level = NotALevel, fv_count = 0 },
-									lb_position = NoPos }],
-							  let_expr = result_expr, let_info_ptr = let_expr_ptr, let_expr_position = NoPos }, expr_heap)
-	transform_pattern_variable {fv_info_ptr,fv_name} No result_expr expr_heap
-		# (var_expr_ptr, expr_heap) = newPtr EI_Empty expr_heap
-		= (Var { var_name = fv_name, var_info_ptr = fv_info_ptr, var_expr_ptr = var_expr_ptr }, result_expr, expr_heap)
 
 initializeContextVariables :: ![TypeContext] !*VarHeap ->  (![TypeContext], !*VarHeap)
 initializeContextVariables contexts var_heap
@@ -2658,7 +750,7 @@ combineDclAndIclModule _ modules icl_decl_symbols icl_definitions icl_sizes cs
 
 	  (moved_dcl_defs, conversion_table, icl_sizes, icl_decl_symbols, cs)
 			= foldSt (add_to_conversion_table dcl_macros.ir_from dcl_common) dcls_local ([], { createArray size NoIndex \\ size <-: dcl_sizes }, icl_sizes, icl_decl_symbols, cs)
-
+            
 	  (new_type_defs, new_class_defs, new_cons_defs, new_selector_defs, new_member_defs, cs)
 			= foldSt (add_dcl_definition dcl_common) moved_dcl_defs ([], [], [], [], [], cs)
 	  cs_symbol_table = removeDeclarationsFromSymbolTable icl_decl_symbols cGlobalScope cs.cs_symbol_table
@@ -2681,7 +773,7 @@ where
 		# (entry=:{ste_kind,ste_index,ste_def_level}, cs_symbol_table) = readPtr id_info cs.cs_symbol_table
 		| ste_kind == STE_Empty
 			# def_index = toInt dcl_kind
-			| can_be_only_in_dcl def_index && not (def_index==cTypeDefs && is_abstract_type dcl_common.com_type_defs dcl_index)
+ 			| can_be_only_in_dcl def_index && not (def_index==cTypeDefs && is_abstract_type dcl_common.com_type_defs dcl_index)
 				# (conversion_table, icl_sizes, icl_defs, cs_symbol_table)
 					= add_dcl_declaration id_info entry decl def_index dcl_index (conversion_table, icl_sizes, icl_defs, cs_symbol_table)
 				= ([ decl : moved_dcl_defs ], conversion_table, icl_sizes, icl_defs, { cs & cs_symbol_table = cs_symbol_table })
@@ -2699,16 +791,16 @@ where
 			# cs_error = checkError "definition module" "conflicting definition in implementation module"
 					(setErrorAdmin (newPosition dcl_ident dcl_pos) cs.cs_error)
 			= (moved_dcl_defs, conversion_table,  icl_sizes, icl_defs, { cs & cs_error = cs_error, cs_symbol_table = cs_symbol_table })
- 
+
 /* To be done : cClassDefs and cMemberDefs */
 
 	can_be_only_in_dcl def_kind
 		=	def_kind == cTypeDefs	|| def_kind == cConstructorDefs || def_kind == cSelectorDefs
 		||	def_kind == cClassDefs	|| def_kind == cMemberDefs
 
-	is_abstract_type com_type_defs dcl_index
-		= case com_type_defs.[dcl_index].td_rhs of (AbstractType _) -> True ; _ -> False
-
+ 	is_abstract_type com_type_defs dcl_index
+ 		= case com_type_defs.[dcl_index].td_rhs of (AbstractType _) -> True ; _ -> False
+ 
 	add_dcl_declaration info_ptr entry dcl def_index dcl_index (conversion_table, icl_sizes, icl_defs, symbol_table)
 		# (icl_index, icl_sizes) = icl_sizes![def_index]
 		=	(	{ conversion_table & [def_index].[dcl_index] = icl_index }
@@ -2722,7 +814,7 @@ where
 			,	[ { dcl & dcl_index = icl_index } : icl_defs ]
 			,	NewEntry symbol_table info_ptr dcl.dcl_kind icl_index cGlobalScope entry
 			)
-
+	
 	add_dcl_definition {com_type_defs} dcl=:{dcl_kind = STE_Type, dcl_index}
 			(new_type_defs, new_class_defs, new_cons_defs, new_selector_defs, new_member_defs, cs)
 		# type_def = com_type_defs.[dcl_index]
@@ -3695,25 +1787,9 @@ addImportsToSymbolTable [{import_module={id_info},import_symbols, import_file_po
 addImportsToSymbolTable [] explicit_akku modules cs
 	= (explicit_akku, modules, cs)
 
-pushErrorAdmin2 _ NoPos cs=:{cs_error={ea_loc=[top_of_stack:_]}}
-	// there is no position info, push current position to balance pop calls
-	= pushErrorAdmin top_of_stack cs
-pushErrorAdmin2 string pos=:(LinePos _ _) cs
-	= pushErrorAdmin (newPosition {id_name=string, id_info=nilPtr} pos) cs
-
 file_and_status {ea_file,ea_ok}
 	= (ea_file, ea_ok)
 
-allocate_bound_var :: !FreeVar !*ExpressionHeap -> (!BoundVar, !.ExpressionHeap)
-allocate_bound_var {fv_name, fv_info_ptr} expr_heap
-	# (var_expr_ptr, expr_heap) = newPtr EI_Empty expr_heap
-	= ({ var_name = fv_name, var_info_ptr = fv_info_ptr, var_expr_ptr = var_expr_ptr }, expr_heap)
-
-allocate_bound_var` :: !Ident !VarInfoPtr !*ExpressionHeap -> (!BoundVar, !.ExpressionHeap)
-allocate_bound_var` fv_name fv_info_ptr expr_heap
-	# (var_expr_ptr, expr_heap) = newPtr EI_Empty expr_heap
-	= ({ var_name = fv_name, var_info_ptr = fv_info_ptr, var_expr_ptr = var_expr_ptr }, expr_heap)
-
 instance <<< FunCall
 where
 	(<<<) file {fc_index} = file <<< fc_index
@@ -3748,11 +1824,6 @@ instance <<< DefinedSymbol
 where
 	(<<<) file { ds_index, ds_ident } = file <<< ds_ident <<< '.' <<< ds_index
 	
-instance <<< FieldSymbol
-where
-	(<<<) file { fs_var } = file <<< fs_var
-
-
 instance <<< Declarations
 where
 //	(<<<) file { dcls_import, dcls_local } = file <<< "I:" <<< dcls_import <<< "L:" <<< dcls_local
@@ -3779,29 +1850,3 @@ instance <<< (Ptr a)
 where
 	(<<<) file ptr = file <<< "[[" <<< ptrToInt ptr <<< "]]"
 
-retrieveGlobalDefinition :: !SymbolTableEntry !STE_Kind !Index -> (!Index, !Index)
-retrieveGlobalDefinition {ste_kind = STE_Imported kind dcl_index, ste_def_level, ste_index} requ_kind mod_index
-	| kind == requ_kind
-		= (ste_index, dcl_index)
-		= (NotFound, mod_index)
-retrieveGlobalDefinition {ste_kind,ste_def_level,ste_index} requ_kind mod_index
-	| ste_kind == requ_kind && ste_def_level == cGlobalScope
-		= (ste_index, mod_index)
-		= (NotFound, mod_index)
-
-/* 2.0 ...
-removeLocalsFromSymbolTable :: !Level ![Ident] !LocalDefs !u:(m a) !*(Heap SymbolTableEntry)
-			-> (!u:(m a), !.Heap SymbolTableEntry) | Array m a & toIdent a
-... */
-removeLocalsFromSymbolTable level loc_vars (CollectedLocalDefs {loc_functions={ir_from,ir_to}}) defs symbol_table
-	= remove_defs_from_symbol_table level ir_from ir_to defs (removeLocalIdentsFromSymbolTable level loc_vars symbol_table)
-where
-	remove_defs_from_symbol_table level from_index to_index defs symbol_table
-		| from_index == to_index
-			= (defs, symbol_table)	
-			#! def = defs.[from_index]
-			   id_info = (toIdent def).id_info
-			   entry = sreadPtr id_info symbol_table
-			| level == entry.ste_def_level
-				= remove_defs_from_symbol_table level (inc from_index) to_index defs (symbol_table <:= (id_info, entry.ste_previous))
-				= remove_defs_from_symbol_table level (inc from_index) to_index defs symbol_table
diff --git a/frontend/checkFunctionBodies.dcl b/frontend/checkFunctionBodies.dcl
new file mode 100644
index 0000000..58ef680
--- /dev/null
+++ b/frontend/checkFunctionBodies.dcl
@@ -0,0 +1,22 @@
+definition module checkFunctionBodies
+
+import syntax, checksupport
+
+::	ExpressionState =
+	{	es_expr_heap	:: !.ExpressionHeap
+	,	es_var_heap			:: !.VarHeap
+	,	es_type_heaps		:: !.TypeHeaps
+	,	es_calls			:: ![FunCall]
+	,	es_dynamics			:: ![ExprInfoPtr]
+	,	es_fun_defs			:: !.{# FunDef}
+	}
+	
+::	ExpressionInput =
+	{	ei_expr_level	:: !Level
+	,	ei_fun_index	:: !Index
+	,	ei_fun_level	:: !Level
+	,	ei_mod_index	:: !Index
+	}
+
+checkFunctionBodies :: !FunctionBody !.ExpressionInput !*ExpressionState !*ExpressionInfo !*CheckState
+					-> (FunctionBody,[FreeVar],!.ExpressionState,.ExpressionInfo,!.CheckState);
diff --git a/frontend/checkFunctionBodies.icl b/frontend/checkFunctionBodies.icl
new file mode 100644
index 0000000..b47282f
--- /dev/null
+++ b/frontend/checkFunctionBodies.icl
@@ -0,0 +1,1953 @@
+implementation module checkFunctionBodies
+
+import syntax, typesupport, parse, checksupport, utilities, checktypes, transform, predef //, RWSDebug
+import explicitimports, comparedefimp
+
+cIsInExpressionList		:== True
+cIsNotInExpressionList	:== False
+
+cEndWithUpdate			:== True
+cEndWithSelection		:== False
+
+::	ExpressionState =
+	{	es_expr_heap	:: !.ExpressionHeap
+	,	es_var_heap			:: !.VarHeap
+	,	es_type_heaps		:: !.TypeHeaps
+	,	es_calls			:: ![FunCall]
+	,	es_dynamics			:: ![ExprInfoPtr]
+	,	es_fun_defs			:: !.{# FunDef}
+	}
+	
+::	ExpressionInput =
+	{	ei_expr_level	:: !Level
+	,	ei_fun_index	:: !Index
+	,	ei_fun_level	:: !Level
+	,	ei_mod_index	:: !Index
+//	,	ei_fun_kind		:: !FunKind
+	}
+
+::	PatternState =
+	{	ps_var_heap :: !.VarHeap
+	,	ps_fun_defs :: !.{# FunDef}
+	}
+
+::	PatternInput =
+	{	pi_def_level		:: !Int
+	,	pi_mod_index		:: !Index
+	,	pi_is_node_pattern	:: !Bool
+	}
+	
+::	ArrayPattern =
+	{	ap_opt_var		:: !Optional (Bind Ident VarInfoPtr)
+	,	ap_array_var	:: !FreeVar
+	,	ap_selections	:: ![Bind FreeVar [ParsedExpr]]
+	}
+
+::	UnfoldMacroState =
+	{	ums_var_heap	:: !.VarHeap
+	,	ums_modules		:: !.{# DclModule}
+	,	ums_cons_defs	:: !.{# ConsDef}
+	,	ums_error		:: !.ErrorAdmin
+	}
+
+::	RecordKind = RK_Constructor | RK_Update | RK_UpdateToConstructor ![AuxiliaryPattern]
+
+checkFunctionBodies :: !FunctionBody !.ExpressionInput !*ExpressionState !*ExpressionInfo !*CheckState -> (FunctionBody,[FreeVar],!.ExpressionState,.ExpressionInfo,!.CheckState);
+checkFunctionBodies (ParsedBody [{pb_args,pb_rhs={rhs_alts,rhs_locals}, pb_position} : bodies]) e_input=:{ei_expr_level,ei_mod_index}
+		e_state=:{es_var_heap, es_fun_defs} e_info cs
+	# (aux_patterns, (var_env, array_patterns), {ps_var_heap, ps_fun_defs}, e_info, cs)
+			= check_patterns pb_args {pi_def_level = ei_expr_level, pi_mod_index = ei_mod_index, pi_is_node_pattern = False} ([], [])
+							{ps_var_heap = es_var_heap, ps_fun_defs = es_fun_defs} e_info cs 
+	  (rhs_expr, free_vars, e_state, e_info, cs)
+	  		= checkRhs [] rhs_alts rhs_locals e_input { e_state & es_var_heap = ps_var_heap, es_fun_defs = ps_fun_defs } e_info cs
+	  (dynamics_in_rhs, e_state)
+	  		= e_state!es_dynamics
+	  (expr_with_array_selections, free_vars, e_state=:{es_var_heap}, e_info, cs)
+			= addArraySelections array_patterns rhs_expr free_vars e_input e_state e_info cs
+	  cs_symbol_table = removeLocalIdentsFromSymbolTable ei_expr_level var_env cs.cs_symbol_table
+	  (cb_args, es_var_heap) = mapSt determine_function_arg aux_patterns es_var_heap
+	  (rhss, free_vars, e_state=:{es_dynamics,es_expr_heap,es_var_heap}, e_info, cs)
+	  		= check_function_bodies free_vars cb_args bodies e_input { e_state & es_dynamics = [], es_var_heap = es_var_heap } e_info
+	  								{ cs & cs_symbol_table = cs_symbol_table }
+	  (rhs, position, es_var_heap, es_expr_heap, dynamics_in_patterns, cs)
+	  		= transform_patterns_into_cases aux_patterns cb_args expr_with_array_selections pb_position es_var_heap es_expr_heap
+	  										dynamics_in_rhs cs
+	= (CheckedBody { cb_args = cb_args, cb_rhs = [{ ca_rhs = rhs, ca_position = position } : rhss] }, free_vars,
+		{ e_state & es_var_heap = es_var_heap, es_expr_heap = es_expr_heap, es_dynamics = dynamics_in_patterns ++ es_dynamics }, e_info, cs)
+where
+	check_patterns [pattern : patterns] p_input accus var_store e_info cs
+		# (aux_pat, accus, var_store, e_info, cs) = checkPattern pattern No p_input accus var_store e_info cs
+		  (aux_pats, accus, var_store, e_info, cs) = check_patterns patterns p_input accus var_store e_info cs
+		= ([aux_pat : aux_pats], accus, var_store, e_info, cs)
+	check_patterns [] p_input accus var_store e_info cs
+		= ([], accus, var_store, e_info, cs)
+
+	determine_function_arg (AP_Variable name var_info (Yes {bind_src, bind_dst})) var_store
+		= ({ fv_name = bind_src, fv_info_ptr = bind_dst, fv_def_level = NotALevel, fv_count = 0 }, var_store)
+	determine_function_arg (AP_Variable name var_info No) var_store
+		= ({ fv_name = name, fv_info_ptr = var_info, fv_def_level = NotALevel, fv_count = 0 }, var_store)
+	determine_function_arg (AP_Algebraic _ _ _ opt_var) var_store
+		# ({bind_src,bind_dst}, var_store) = determinePatternVariable opt_var var_store
+		= ({ fv_name = bind_src, fv_info_ptr = bind_dst, fv_def_level = NotALevel, fv_count = 0 }, var_store)
+	determine_function_arg (AP_Basic _ opt_var) var_store
+		# ({bind_src,bind_dst}, var_store) = determinePatternVariable opt_var var_store
+		= ({ fv_name = bind_src, fv_info_ptr = bind_dst, fv_def_level = NotALevel, fv_count = 0 }, var_store)
+	determine_function_arg (AP_Dynamic _ _ opt_var) var_store
+		# ({bind_src,bind_dst}, var_store) = determinePatternVariable opt_var var_store
+		= ({ fv_name = bind_src, fv_info_ptr = bind_dst, fv_def_level = NotALevel, fv_count = 0 }, var_store)
+	determine_function_arg _ var_store
+		# ({bind_src,bind_dst}, var_store) = determinePatternVariable No var_store
+		= ({ fv_name = bind_src, fv_info_ptr = bind_dst, fv_def_level = NotALevel, fv_count = 0 }, var_store)
+	
+	check_function_bodies free_vars fun_args [{pb_args,pb_rhs={rhs_alts,rhs_locals},pb_position} : bodies]
+							e_input=:{ei_expr_level,ei_mod_index} e_state=:{es_var_heap,es_fun_defs} e_info cs
+		# (aux_patterns, (var_env, array_patterns), {ps_var_heap, ps_fun_defs}, e_info, cs)
+				= check_patterns pb_args { pi_def_level = ei_expr_level, pi_mod_index = ei_mod_index, pi_is_node_pattern = False } ([], [])
+					{ps_var_heap = es_var_heap, ps_fun_defs = es_fun_defs} e_info cs
+		  e_state = { e_state & es_var_heap = ps_var_heap, es_fun_defs = ps_fun_defs}
+		  (rhs_expr, free_vars, e_state, e_info, cs) = checkRhs free_vars rhs_alts rhs_locals e_input e_state e_info cs
+		  (rhs_expr, free_vars, e_state=:{es_dynamics=dynamics_in_rhs}, e_info, cs)
+				= addArraySelections array_patterns rhs_expr free_vars e_input e_state e_info cs
+	 	  cs_symbol_table = removeLocalIdentsFromSymbolTable ei_expr_level var_env cs.cs_symbol_table
+		  (rhs_exprs, free_vars, e_state=:{es_dynamics,es_expr_heap,es_var_heap}, e_info, cs)
+		  		= check_function_bodies free_vars fun_args bodies e_input { e_state & es_dynamics = [] } e_info { cs & cs_symbol_table = cs_symbol_table }
+		  (rhs_expr, position, es_var_heap, es_expr_heap, dynamics_in_patterns, cs)
+		  		= transform_patterns_into_cases aux_patterns fun_args rhs_expr pb_position
+		  										 es_var_heap es_expr_heap dynamics_in_rhs cs
+		= ([{ ca_rhs = rhs_expr, ca_position = position } : rhs_exprs], free_vars,
+			{ e_state & es_var_heap = es_var_heap, es_expr_heap = es_expr_heap,
+			es_dynamics = dynamics_in_patterns ++ es_dynamics }, e_info, cs)
+	check_function_bodies free_vars fun_args [] e_input e_state e_info cs
+		= ([], free_vars, e_state, e_info, cs) 
+		
+	transform_patterns_into_cases [pattern : patterns] [fun_arg : fun_args] result_expr pattern_position
+									var_store expr_heap opt_dynamics cs
+		# (patterns_expr, pattern_position, var_store, expr_heap, opt_dynamics, cs)
+				= transform_succeeding_patterns_into_cases patterns fun_args result_expr pattern_position
+															var_store expr_heap opt_dynamics cs
+		= transform_pattern_into_cases pattern fun_arg patterns_expr pattern_position var_store expr_heap opt_dynamics cs
+	where
+		transform_succeeding_patterns_into_cases [] _ result_expr pattern_position var_store expr_heap opt_dynamics cs
+			= (result_expr, pattern_position, var_store, expr_heap, opt_dynamics, cs)
+		transform_succeeding_patterns_into_cases [pattern : patterns] [fun_arg : fun_args] result_expr pattern_position
+												var_store expr_heap opt_dynamics cs
+			# (patterns_expr, pattern_position, var_store, expr_heap, opt_dynamics, cs)
+				= transform_succeeding_patterns_into_cases patterns fun_args result_expr pattern_position
+															var_store expr_heap opt_dynamics cs
+			= transform_pattern_into_cases pattern fun_arg patterns_expr pattern_position var_store expr_heap opt_dynamics cs
+
+	transform_patterns_into_cases [] _ result_expr pattern_position var_store expr_heap opt_dynamics cs
+		= (result_expr, pattern_position, var_store, expr_heap, opt_dynamics, cs)
+
+	transform_pattern_into_cases :: !AuxiliaryPattern !FreeVar !Expression !Position !*VarHeap !*ExpressionHeap ![DynamicPtr] !*CheckState
+		-> (!Expression, !Position, !*VarHeap, !*ExpressionHeap, ![DynamicPtr], !*CheckState)
+	transform_pattern_into_cases (AP_Variable name var_info opt_var) fun_arg=:{fv_info_ptr,fv_name} result_expr pattern_position
+									var_store expr_heap opt_dynamics cs
+		= case opt_var of
+			Yes {bind_src, bind_dst}
+				| bind_dst == fv_info_ptr
+					# (var_expr_ptr, expr_heap) = newPtr EI_Empty expr_heap
+					  (let_expr_ptr, expr_heap) = newPtr EI_Empty expr_heap
+					-> (Let { let_strict_binds = [], let_lazy_binds= [
+								{ lb_src = Var { var_name = fv_name, var_info_ptr = fv_info_ptr, var_expr_ptr = var_expr_ptr },
+									lb_dst = { fv_name = name, fv_info_ptr = var_info, fv_def_level = NotALevel, fv_count = 0 },
+									lb_position = NoPos }],
+							  let_expr = result_expr, let_info_ptr = let_expr_ptr, let_expr_position = NoPos }, 
+						pattern_position, var_store, expr_heap, opt_dynamics, cs)
+					# (var_expr_ptr1, expr_heap) = newPtr EI_Empty expr_heap
+					  (var_expr_ptr2, expr_heap) = newPtr EI_Empty expr_heap
+					  (let_expr_ptr, expr_heap) = newPtr EI_Empty expr_heap
+					-> (Let { let_strict_binds = [], let_lazy_binds= [
+								{ lb_src = Var { var_name = fv_name, var_info_ptr = fv_info_ptr, var_expr_ptr = var_expr_ptr1 },
+									lb_dst = { fv_name = name, fv_info_ptr = var_info, fv_def_level = NotALevel, fv_count = 0 },
+									lb_position = NoPos },
+								{ lb_src = Var { var_name = fv_name, var_info_ptr = fv_info_ptr, var_expr_ptr = var_expr_ptr2 },
+									lb_dst = { fv_name = bind_src, fv_info_ptr = bind_dst, fv_def_level = NotALevel, fv_count = 0 },
+									lb_position = NoPos }],
+							  let_expr = result_expr, let_info_ptr = let_expr_ptr, let_expr_position = NoPos }, 
+						pattern_position, var_store, expr_heap, opt_dynamics, cs)
+			No
+				| var_info == fv_info_ptr
+					-> (result_expr, pattern_position, var_store, expr_heap, opt_dynamics, cs)
+					# (var_expr_ptr, expr_heap) = newPtr EI_Empty expr_heap
+					  (let_expr_ptr, expr_heap) = newPtr EI_Empty expr_heap
+					-> (Let { let_strict_binds = [], let_lazy_binds=
+									[{ lb_src = Var { var_name = fv_name, var_info_ptr = fv_info_ptr, var_expr_ptr = var_expr_ptr },
+										 lb_dst = { fv_name = name, fv_info_ptr = var_info, fv_def_level = NotALevel, fv_count = 0 },
+										 lb_position = NoPos }],
+							  let_expr = result_expr, let_info_ptr = let_expr_ptr, let_expr_position = NoPos },
+						pattern_position, var_store, expr_heap, opt_dynamics, cs)
+
+	transform_pattern_into_cases (AP_Algebraic cons_symbol type_index args opt_var) fun_arg result_expr pattern_position
+									var_store expr_heap opt_dynamics cs
+		# (var_args, result_expr, pattern_position, var_store, expr_heap, opt_dynamics, cs)
+				= convertSubPatterns args result_expr pattern_position var_store expr_heap opt_dynamics cs
+		  type_symbol = {glob_module = cons_symbol.glob_module, glob_object = type_index}
+	  	  (act_var, result_expr, expr_heap) = transform_pattern_variable fun_arg opt_var result_expr expr_heap
+		  alg_pattern = { ap_symbol = cons_symbol, ap_vars = var_args, ap_expr = result_expr, ap_position = pattern_position }
+	  	  case_guards = AlgebraicPatterns type_symbol [alg_pattern]
+		  (case_expr_ptr, expr_heap) = newPtr EI_Empty expr_heap
+		= (Case { case_expr = act_var, case_guards = case_guards, case_default = No, case_ident = No,
+				case_info_ptr = case_expr_ptr, case_default_pos = NoPos },
+				NoPos, var_store, expr_heap, opt_dynamics, cs)	
+	transform_pattern_into_cases (AP_Basic basic_val opt_var) fun_arg result_expr pattern_position var_store expr_heap opt_dynamics cs
+		# (basic_type, cs) = typeOfBasicValue basic_val cs
+	  	  (act_var, result_expr, expr_heap) = transform_pattern_variable fun_arg opt_var result_expr expr_heap
+		  case_guards = BasicPatterns basic_type [{ bp_value = basic_val, bp_expr = result_expr, bp_position = pattern_position }]
+		  (case_expr_ptr, expr_heap) = newPtr EI_Empty expr_heap
+		= (Case { case_expr = act_var, case_guards = case_guards, case_default = No, case_ident = No,
+					case_info_ptr = case_expr_ptr, case_default_pos = NoPos },
+			NoPos, var_store, expr_heap, opt_dynamics, cs)	
+	transform_pattern_into_cases (AP_Dynamic pattern type opt_var) fun_arg result_expr pattern_position var_store expr_heap opt_dynamics cs
+		# (var_arg, result_expr, pattern_position, var_store, expr_heap, opt_dynamics, cs)
+				= convertSubPattern pattern result_expr pattern_position var_store expr_heap opt_dynamics cs
+		  (type_case_info_ptr, expr_heap) = newPtr EI_Empty expr_heap
+		  (dynamic_info_ptr, expr_heap) = newPtr (EI_DynamicType type opt_dynamics) expr_heap
+	  	  (act_var, result_expr, expr_heap) = transform_pattern_variable fun_arg opt_var result_expr expr_heap
+	  	  type_case_patterns = [{ dp_var = var_arg, dp_type	= dynamic_info_ptr,	dp_rhs = result_expr, dp_type_patterns_vars = [],
+	  	  							dp_type_code = TCE_Empty, dp_position = pattern_position }]
+		= (buildTypeCase act_var type_case_patterns No type_case_info_ptr, NoPos, var_store, expr_heap, [dynamic_info_ptr], cs)	
+	transform_pattern_into_cases (AP_WildCard _) fun_arg result_expr pattern_position var_store expr_heap opt_dynamics cs
+		= (result_expr, pattern_position, var_store, expr_heap, opt_dynamics, cs)	
+	transform_pattern_into_cases (AP_Empty name) fun_arg result_expr pattern_position var_store expr_heap opt_dynamics cs
+		= (result_expr, pattern_position, var_store, expr_heap, opt_dynamics, cs)
+
+	transform_pattern_variable :: !FreeVar !(Optional !(Bind Ident VarInfoPtr)) !Expression !*ExpressionHeap
+		-> (!Expression, !Expression, !*ExpressionHeap)
+	transform_pattern_variable {fv_info_ptr,fv_name} (Yes {bind_src,bind_dst}) result_expr expr_heap
+		| bind_dst == fv_info_ptr
+			# (var_expr_ptr, expr_heap) = newPtr EI_Empty expr_heap
+			= (Var { var_name = fv_name, var_info_ptr = fv_info_ptr, var_expr_ptr = var_expr_ptr }, result_expr, expr_heap)
+			# (var_expr_ptr1, expr_heap) = newPtr EI_Empty expr_heap
+			  (var_expr_ptr2, expr_heap) = newPtr EI_Empty expr_heap
+			  (let_expr_ptr, expr_heap) = newPtr EI_Empty expr_heap
+			= (Var { var_name = fv_name, var_info_ptr = fv_info_ptr, var_expr_ptr = var_expr_ptr1 },
+						Let { let_strict_binds = [], let_lazy_binds =
+						 		[{ lb_src = Var { var_name = fv_name, var_info_ptr = fv_info_ptr, var_expr_ptr = var_expr_ptr2 },
+									lb_dst = { fv_name = bind_src, fv_info_ptr = bind_dst, fv_def_level = NotALevel, fv_count = 0 },
+									lb_position = NoPos }],
+							  let_expr = result_expr, let_info_ptr = let_expr_ptr, let_expr_position = NoPos }, expr_heap)
+	transform_pattern_variable {fv_info_ptr,fv_name} No result_expr expr_heap
+		# (var_expr_ptr, expr_heap) = newPtr EI_Empty expr_heap
+		= (Var { var_name = fv_name, var_info_ptr = fv_info_ptr, var_expr_ptr = var_expr_ptr }, result_expr, expr_heap)
+
+checkRhs :: [FreeVar] OptGuardedAlts LocalDefs ExpressionInput *ExpressionState *ExpressionInfo *CheckState -> *(!Expression,![FreeVar],!*ExpressionState,!*ExpressionInfo,!*CheckState);
+checkRhs free_vars rhs_alts rhs_locals e_input=:{ei_expr_level,ei_mod_index} e_state e_info cs
+	# ei_expr_level = inc ei_expr_level
+	  (loc_defs, (var_env, array_patterns), e_state, e_info, cs) = checkLhssOfLocalDefs ei_expr_level ei_mod_index rhs_locals e_state e_info cs
+	  (es_fun_defs, e_info, heaps, cs)
+	  		= checkLocalFunctions ei_mod_index ei_expr_level rhs_locals e_state.es_fun_defs e_info
+	  			{ hp_var_heap = e_state.es_var_heap, hp_expression_heap = e_state.es_expr_heap, hp_type_heaps = e_state.es_type_heaps } cs
+	  (rhs_expr, free_vars, e_state, e_info, cs) 
+	  		= check_opt_guarded_alts free_vars rhs_alts { e_input & ei_expr_level = ei_expr_level }
+	  			{ e_state & es_fun_defs = es_fun_defs, es_var_heap = heaps.hp_var_heap, es_expr_heap = heaps.hp_expression_heap,
+					es_type_heaps = heaps.hp_type_heaps } e_info cs
+	  (expr, free_vars, e_state, e_info, cs)
+			= addArraySelections array_patterns rhs_expr free_vars e_input e_state e_info cs
+	  (expr, free_vars, e_state, e_info, cs) = checkRhssAndTransformLocalDefs free_vars loc_defs expr e_input e_state e_info cs
+	  (es_fun_defs, cs_symbol_table) = removeLocalsFromSymbolTable ei_expr_level var_env rhs_locals e_state.es_fun_defs cs.cs_symbol_table
+	= (expr, free_vars, { e_state & es_fun_defs = es_fun_defs}, e_info, { cs & cs_symbol_table = cs_symbol_table })
+where
+	check_opt_guarded_alts free_vars (GuardedAlts guarded_alts default_expr) e_input e_state e_info cs
+		# (let_vars_list, rev_guarded_exprs, last_expr_level, free_vars, e_state, e_info, cs)
+				= check_guarded_expressions free_vars guarded_alts [] [] e_input e_state e_info cs
+		  (default_expr, free_vars, e_state, e_info, cs)
+		  		= check_default_expr free_vars default_expr { e_input & ei_expr_level = last_expr_level } e_state e_info cs
+		  cs = { cs & cs_symbol_table = remove_seq_let_vars e_input.ei_expr_level let_vars_list cs.cs_symbol_table }
+	  	  (_, result_expr, es_expr_heap) = convert_guards_to_cases rev_guarded_exprs default_expr e_state.es_expr_heap
+	  	= (result_expr, free_vars, { e_state & es_expr_heap = es_expr_heap }, e_info, cs)
+	check_opt_guarded_alts free_vars (UnGuardedExpr unguarded_expr) e_input e_state e_info cs
+		= check_unguarded_expression free_vars unguarded_expr e_input e_state e_info cs
+
+	check_default_expr free_vars (Yes default_expr) e_input e_state e_info cs
+		# (expr, free_vars, e_state, e_info, cs) = check_unguarded_expression free_vars default_expr e_input e_state e_info cs
+		= (Yes expr, free_vars, e_state, e_info, cs)
+	check_default_expr free_vars No e_input e_state e_info cs
+		= (No, free_vars, e_state, e_info, cs)
+		
+	convert_guards_to_cases [(let_binds, guard, expr, guard_ident)] result_expr es_expr_heap
+		# (case_expr_ptr, es_expr_heap) = newPtr EI_Empty es_expr_heap
+		  basic_pattern = {bp_value = (BVB True), bp_expr = expr, bp_position = NoPos }
+		  case_expr = Case { case_expr = guard, case_guards = BasicPatterns BT_Bool [basic_pattern],
+		  		case_default = result_expr, case_ident = Yes guard_ident,
+		  		case_info_ptr = case_expr_ptr, case_default_pos = NoPos }
+		= build_sequential_lets let_binds case_expr NoPos es_expr_heap
+	convert_guards_to_cases [(let_binds, guard, expr, guard_ident) : rev_guarded_exprs] result_expr es_expr_heap
+		# (case_expr_ptr, es_expr_heap) = newPtr EI_Empty es_expr_heap
+		  basic_pattern = {bp_value = (BVB True), bp_expr = expr, bp_position = NoPos }
+		  case_expr = Case { case_expr = guard, case_guards = BasicPatterns BT_Bool [basic_pattern],
+		  		case_default = result_expr, case_ident = Yes guard_ident,
+		  		case_info_ptr = case_expr_ptr, case_default_pos = NoPos }
+		  (_, result_expr, es_expr_heap) = build_sequential_lets let_binds case_expr NoPos es_expr_heap
+		= convert_guards_to_cases rev_guarded_exprs (Yes result_expr) es_expr_heap
+	
+	check_guarded_expressions free_vars [gexpr : gexprs] let_vars_list rev_guarded_exprs e_input e_state e_info cs
+		# (let_vars_list, rev_guarded_exprs, ei_expr_level, free_vars, e_state, e_info, cs)
+				= check_guarded_expression free_vars gexpr let_vars_list rev_guarded_exprs e_input e_state e_info cs
+		= check_guarded_expressions free_vars gexprs let_vars_list rev_guarded_exprs { e_input & ei_expr_level = ei_expr_level } e_state e_info cs
+	check_guarded_expressions free_vars [] let_vars_list rev_guarded_exprs {ei_expr_level} e_state e_info cs
+		= (let_vars_list, rev_guarded_exprs, ei_expr_level, free_vars, e_state, e_info, cs)
+
+	check_guarded_expression free_vars {alt_nodes,alt_guard,alt_expr,alt_ident,alt_position}
+			let_vars_list rev_guarded_exprs e_input=:{ei_expr_level,ei_mod_index} e_state e_info cs
+		# (let_binds, let_vars_list, ei_expr_level, free_vars, e_state, e_info, cs) = check_sequential_lets free_vars alt_nodes let_vars_list
+		  		{ e_input & ei_expr_level = inc ei_expr_level } e_state e_info cs
+		  e_input = { e_input & ei_expr_level = ei_expr_level }
+		  cs = pushErrorAdmin2 "guard" alt_position cs
+	  	  (guard, free_vars, e_state, e_info, cs) = checkExpression free_vars alt_guard e_input e_state e_info cs
+		  cs = popErrorAdmin cs
+		  (expr, free_vars, e_state, e_info, cs) = check_opt_guarded_alts free_vars alt_expr e_input e_state e_info cs
+	  	= (let_vars_list, [(let_binds, guard, expr, alt_ident) : rev_guarded_exprs], ei_expr_level, free_vars, e_state, e_info,  cs )
+
+	check_unguarded_expression :: [FreeVar] ExprWithLocalDefs ExpressionInput *ExpressionState *ExpressionInfo *CheckState -> *(!Expression,![FreeVar],!*ExpressionState,!*ExpressionInfo,!*CheckState);
+	check_unguarded_expression free_vars {ewl_nodes,ewl_expr,ewl_locals,ewl_position} e_input=:{ei_expr_level,ei_mod_index} e_state e_info cs
+		# this_expr_level = inc ei_expr_level
+		  (loc_defs, (var_env, array_patterns), e_state, e_info, cs)
+		 		= checkLhssOfLocalDefs this_expr_level ei_mod_index ewl_locals e_state e_info cs
+		  (binds, let_vars_list, rhs_expr_level, free_vars, e_state, e_info, cs) = check_sequential_lets free_vars ewl_nodes [] { e_input & ei_expr_level = this_expr_level } e_state e_info cs
+		  cs = pushErrorAdmin2 "" ewl_position cs
+	  	  (expr, free_vars, e_state, e_info, cs) = checkExpression free_vars ewl_expr { e_input & ei_expr_level = rhs_expr_level } e_state e_info cs
+		  cs = popErrorAdmin cs
+		  (expr, free_vars, e_state, e_info, cs)
+				= addArraySelections array_patterns expr free_vars e_input e_state e_info cs
+		  cs = { cs & cs_symbol_table = remove_seq_let_vars rhs_expr_level let_vars_list cs.cs_symbol_table }
+		  (_, seq_let_expr, es_expr_heap) = build_sequential_lets binds expr ewl_position e_state.es_expr_heap
+	  	  (expr, free_vars, e_state, e_info, cs)
+				= checkRhssAndTransformLocalDefs free_vars loc_defs seq_let_expr e_input { e_state & es_expr_heap = es_expr_heap} e_info cs
+	  	  (es_fun_defs, e_info, heaps, cs)
+	  	  		= checkLocalFunctions ei_mod_index rhs_expr_level ewl_locals e_state.es_fun_defs e_info 
+	  	  		{ hp_var_heap = e_state.es_var_heap, hp_expression_heap = e_state.es_expr_heap, hp_type_heaps = e_state.es_type_heaps } cs
+		  (es_fun_defs, cs_symbol_table) = removeLocalsFromSymbolTable this_expr_level var_env ewl_locals es_fun_defs cs.cs_symbol_table
+	  	= (expr, free_vars, {e_state & es_fun_defs = es_fun_defs, es_var_heap = heaps.hp_var_heap,
+	  			es_expr_heap = heaps.hp_expression_heap, es_type_heaps = heaps.hp_type_heaps }, e_info, { cs & cs_symbol_table = cs_symbol_table} )
+	
+	remove_seq_let_vars level [] symbol_table
+		= symbol_table
+	remove_seq_let_vars level [let_vars : let_vars_list] symbol_table
+		= remove_seq_let_vars (dec level) let_vars_list (removeLocalIdentsFromSymbolTable level let_vars symbol_table)
+	
+	check_sequential_lets :: [FreeVar] [NodeDefWithLocals] u:[[Ident]] !ExpressionInput *ExpressionState *ExpressionInfo *CheckState 
+						-> *(![.([LetBind],![LetBind])],!u:[[Ident]],!Int,![FreeVar],!*ExpressionState,!*ExpressionInfo,!*CheckState);
+	check_sequential_lets free_vars [seq_let:seq_lets] let_vars_list e_input=:{ei_expr_level,ei_mod_index} e_state e_info cs
+		# ei_expr_level
+				= inc ei_expr_level
+		  e_input
+		  		= { e_input & ei_expr_level = ei_expr_level }
+		  (src_expr, pattern_expr, (let_vars, array_patterns), free_vars, e_state, e_info, cs)
+		  		= check_sequential_let free_vars seq_let e_input e_state e_info cs
+	      (binds, loc_envs, max_expr_level, free_vars, e_state, e_info, cs)
+	      		= check_sequential_lets free_vars seq_lets [let_vars : let_vars_list] e_input e_state e_info cs
+		  (let_binds, es_var_heap, es_expr_heap, e_info, cs)
+				= transfromPatternIntoBind ei_mod_index ei_expr_level pattern_expr src_expr seq_let.ndwl_position
+						e_state.es_var_heap e_state.es_expr_heap e_info cs
+		  e_state
+		  		= { e_state & es_var_heap = es_var_heap, es_expr_heap = es_expr_heap }
+		  (strict_array_pattern_binds, lazy_array_pattern_binds, free_vars, e_state, e_info, cs)
+				= foldSt (buildSelections e_input) array_patterns ([], [], free_vars, e_state, e_info, cs)
+		  all_binds
+		  		= [if seq_let.ndwl_strict (s, l) ([],let_binds), (strict_array_pattern_binds, lazy_array_pattern_binds) : binds]
+		    with (l,s) = splitAt ((length let_binds)-1) let_binds
+	    = (all_binds, loc_envs, max_expr_level, free_vars, e_state, e_info, cs)
+	check_sequential_lets free_vars [] let_vars_list e_input=:{ei_expr_level} e_state e_info cs
+		= ([], let_vars_list, ei_expr_level, free_vars, e_state, e_info, cs)
+
+	check_sequential_let :: [FreeVar] NodeDefWithLocals ExpressionInput *ExpressionState *ExpressionInfo *CheckState -> *(!Expression,!AuxiliaryPattern,!(![Ident],![ArrayPattern]),![FreeVar],!*ExpressionState,!*ExpressionInfo,!*CheckState);
+	check_sequential_let free_vars {ndwl_def={bind_src,bind_dst},ndwl_locals, ndwl_position} e_input=:{ei_expr_level,ei_mod_index} e_state e_info cs
+		# cs = pushErrorAdmin (newPosition {id_name="node definition", id_info=nilPtr} ndwl_position) cs
+		  (loc_defs, (loc_env, loc_array_patterns), e_state, e_info, cs) = checkLhssOfLocalDefs ei_expr_level ei_mod_index ndwl_locals e_state e_info cs
+		  (src_expr, free_vars, e_state, e_info, cs) = checkExpression free_vars bind_src e_input e_state e_info cs
+		  (src_expr, free_vars, e_state, e_info, cs)
+				= addArraySelections loc_array_patterns src_expr free_vars e_input e_state e_info cs
+		  (src_expr, free_vars, e_state, e_info, cs) = checkRhssAndTransformLocalDefs free_vars loc_defs src_expr e_input e_state e_info cs
+		  (es_fun_defs, e_info, {hp_var_heap,hp_expression_heap,hp_type_heaps}, cs)
+				= checkLocalFunctions ei_mod_index ei_expr_level ndwl_locals e_state.es_fun_defs e_info
+	  				{ hp_var_heap = e_state.es_var_heap, hp_expression_heap = e_state.es_expr_heap, hp_type_heaps = e_state.es_type_heaps } cs
+	  	  (es_fun_defs, cs_symbol_table) = removeLocalsFromSymbolTable ei_expr_level loc_env ndwl_locals es_fun_defs cs.cs_symbol_table
+		  (pattern, accus, {ps_fun_defs,ps_var_heap}, e_info, cs)
+				= checkPattern bind_dst No { pi_def_level = ei_expr_level, pi_mod_index = ei_mod_index, pi_is_node_pattern = True } ([], []) 
+					{ps_var_heap = hp_var_heap, ps_fun_defs = es_fun_defs } e_info { cs & cs_symbol_table = cs_symbol_table }
+		  e_state = { e_state & es_var_heap = ps_var_heap, es_expr_heap = hp_expression_heap, es_type_heaps = hp_type_heaps, es_fun_defs = ps_fun_defs }
+		= (src_expr, pattern, accus, free_vars, e_state, e_info, popErrorAdmin cs)
+	
+	build_sequential_lets :: ![(![LetBind],![LetBind])] !Expression !Position !*ExpressionHeap -> (!Position, !Expression, !*ExpressionHeap)
+	build_sequential_lets [] expr let_expr_position expr_heap
+		= (let_expr_position, expr, expr_heap)
+	build_sequential_lets [(strict_binds, lazy_binds) : seq_lets] expr let_expr_position expr_heap
+		# (let_expr_position, let_expr, expr_heap) = build_sequential_lets seq_lets expr let_expr_position expr_heap
+	  	  (let_expr, expr_heap) = buildLetExpression strict_binds lazy_binds let_expr let_expr_position expr_heap
+		= (if (isEmpty strict_binds && isEmpty lazy_binds) let_expr_position NoPos, let_expr, expr_heap)
+
+checkExpression :: ![FreeVar] !ParsedExpr !ExpressionInput !*ExpressionState !*ExpressionInfo !*CheckState
+	-> *(!Expression, ![FreeVar], !*ExpressionState, !*ExpressionInfo, !*CheckState);
+checkExpression free_vars (PE_List exprs) e_input e_state e_info cs	
+	# (exprs, free_vars, e_state, e_info, cs) = check_expressions free_vars exprs e_input e_state e_info cs
+	  (expr, e_state, cs_error) = build_expression exprs e_state cs.cs_error
+	= (expr, free_vars, e_state, e_info, { cs & cs_error = cs_error })
+
+where
+	check_expressions free_vars [expr : exprs] e_input e_state e_info cs
+		# (exprs, free_vars, e_state, e_info, cs) = check_expressions free_vars exprs e_input e_state e_info cs
+		= case expr of
+			PE_Ident id
+				# (expr, free_vars, e_state, e_info, cs) = checkIdentExpression cIsInExpressionList free_vars id e_input e_state e_info cs
+ 				-> ([expr : exprs], free_vars, e_state, e_info, cs)
+ 			_
+				# (expr, free_vars, e_state, e_info, cs) = checkExpression free_vars expr e_input e_state e_info cs
+ 				-> ([expr : exprs], free_vars, e_state, e_info, cs)
+ 	check_expressions free_vars [] e_input e_state e_info cs
+		= ([], free_vars, e_state, e_info, cs)
+
+	first_argument_of_infix_operator_missing
+		= "first argument of infix operator missing"
+
+	build_expression [Constant symb _ (Prio _ _) _ , _: _] e_state cs_error
+		= (EE, e_state, checkError symb.symb_name first_argument_of_infix_operator_missing cs_error)
+	build_expression [Constant symb arity _ is_fun] e_state cs_error
+		= buildApplication symb arity 0 is_fun [] e_state cs_error
+	build_expression [expr] e_state cs_error
+		= (expr, e_state, cs_error)
+	build_expression [expr : exprs] e_state cs_error
+		# (opt_opr, left, e_state, cs_error) = split_at_operator [expr] exprs e_state cs_error
+		  (left_expr, e_state, cs_error) = combine_expressions left [] 0 e_state cs_error
+		= case opt_opr of
+			Yes (symb, prio, is_fun, right)
+				-> case right of
+					[Constant symb _ (Prio _ _) _:_]
+						-> (EE, e_state, checkError symb.symb_name first_argument_of_infix_operator_missing cs_error)
+					_
+						-> build_operator_expression [] left_expr (symb, prio, is_fun) right e_state cs_error
+			No
+				-> (left_expr, e_state, cs_error)
+	where
+		split_at_operator left [Constant symb arity NoPrio is_fun : exprs] e_state cs_error
+			# (appl_exp, e_state, cs_error) = buildApplication symb arity 0 is_fun [] e_state cs_error
+			= split_at_operator [appl_exp : left] exprs e_state cs_error
+		split_at_operator left [Constant symb arity (Prio _ _) is_fun] e_state cs_error
+			= (No, left, e_state, checkError symb.symb_name "second argument of infix operator missing" cs_error)
+		split_at_operator left [Constant symb arity prio is_fun] e_state cs_error
+			# (appl_exp, e_state, cs_error) = buildApplication symb arity 0 is_fun [] e_state cs_error
+			= (No, [appl_exp : left], e_state, cs_error)
+		split_at_operator left [expr=:(Constant symb _ prio is_fun) : exprs] e_state cs_error
+			= (Yes (symb, prio, is_fun, exprs), left, e_state, cs_error)
+		split_at_operator left [expr : exprs] e_state cs_error
+			= split_at_operator [expr : left] exprs e_state cs_error
+		split_at_operator exp [] e_state cs_error
+			= (No, exp, e_state, cs_error)
+
+		combine_expressions [first_expr] args arity e_state cs_error
+			= case first_expr of
+				Constant symb form_arity _ is_fun
+					# (app_exp, e_state, cs_error) = buildApplication symb form_arity arity is_fun args e_state cs_error
+					-> (app_exp, e_state, cs_error)
+				_
+					| arity == 0
+						-> (first_expr, e_state, cs_error)
+						-> (first_expr @ args, e_state, cs_error)
+		combine_expressions [rev_arg : rev_args] args arity e_state cs_error
+			= combine_expressions rev_args [rev_arg : args] (inc arity) e_state cs_error
+		
+
+ 		build_operator_expression left_appls left1 (symb1, prio1, is_fun1) [re : res] e_state cs_error
+			# (opt_opr, left2, e_state, cs_error) = split_at_operator [re] res e_state cs_error
+			= case opt_opr of
+				Yes (symb2, prio2, is_fun2, right)
+					# optional_prio = determinePriority prio1 prio2
+					-> case optional_prio of
+						Yes priority
+							| priority
+						  		# (middle_exp, e_state, cs_error) = combine_expressions left2 [] 0 e_state cs_error
+								  (new_left, e_state, cs_error) = buildApplication symb1 2 2 is_fun1 [left1,middle_exp] e_state cs_error
+								  (left_appls, new_left, e_state, cs_error) = build_left_operand left_appls prio2 new_left e_state cs_error
+								-> build_operator_expression left_appls new_left (symb2, prio2, is_fun2) right e_state cs_error
+						  		# (middle_exp, e_state, cs_error) = combine_expressions left2 [] 0 e_state cs_error
+								-> build_operator_expression [(symb1, prio1, is_fun1, left1) : left_appls]
+										middle_exp (symb2, prio2, is_fun2) right e_state cs_error
+						No
+							-> (EE, e_state, checkError symb1.symb_name "conflicting priorities" cs_error)
+				No
+					# (right, e_state, cs_error) = combine_expressions left2 [] 0 e_state cs_error
+					  (result_expr, e_state, cs_error) = buildApplication symb1 2 2 is_fun1 [left1,right] e_state cs_error
+					-> build_final_expression left_appls result_expr e_state cs_error
+
+		build_left_operand [] _ result_expr e_state cs_error
+			= ([], result_expr, e_state, cs_error)		
+		build_left_operand la=:[(symb, priol, is_fun, left) : left_appls] prior result_expr e_state cs_error
+			# optional_prio = determinePriority priol prior
+			= case optional_prio of
+				Yes priority
+					| priority
+						# (result_expr, e_state, cs_error) = buildApplication symb 2 2 is_fun [left,result_expr] e_state cs_error
+						-> build_left_operand left_appls prior result_expr e_state cs_error
+						-> (la, result_expr, e_state, cs_error)
+				No
+					-> (la, EE, e_state, checkError symb.symb_name "conflicting priorities" cs_error)
+		
+		build_final_expression [] result_expr e_state cs_error
+			= (result_expr, e_state, cs_error)		
+		build_final_expression [(symb, _, is_fun, left) : left_appls] result_expr e_state cs_error
+			# (result_expr, e_state, cs_error) = buildApplication symb 2 2 is_fun [left,result_expr] e_state cs_error
+			= build_final_expression left_appls result_expr e_state cs_error
+					
+checkExpression free_vars (PE_Let strict let_locals expr) e_input=:{ei_expr_level,ei_mod_index} e_state e_info cs
+	# ei_expr_level = inc ei_expr_level
+	  (loc_defs, (var_env, array_patterns), e_state, e_info, cs)
+	  		= checkLhssOfLocalDefs ei_expr_level ei_mod_index let_locals e_state e_info cs
+	  e_input = { e_input & ei_expr_level = ei_expr_level }
+	  (let_expr, free_vars, e_state, e_info, cs) = checkExpression free_vars expr e_input e_state e_info cs
+	  (expr, free_vars, e_state=:{es_dynamics,es_expr_heap,es_var_heap}, e_info, cs)
+			= addArraySelections array_patterns let_expr free_vars e_input e_state e_info cs
+	  (expr, free_vars, e_state, e_info, cs) = checkRhssAndTransformLocalDefs free_vars loc_defs expr e_input e_state e_info cs
+	  (es_fun_defs, e_info, heaps, cs)
+			= checkLocalFunctions ei_mod_index ei_expr_level let_locals e_state.es_fun_defs e_info
+	  			{ hp_var_heap = e_state.es_var_heap, hp_expression_heap = e_state.es_expr_heap, hp_type_heaps = e_state.es_type_heaps } cs
+	  (es_fun_defs, cs_symbol_table) = removeLocalsFromSymbolTable ei_expr_level var_env let_locals es_fun_defs cs.cs_symbol_table
+	= (expr, free_vars,
+		{ e_state & es_fun_defs = es_fun_defs, es_var_heap = heaps.hp_var_heap, es_expr_heap = heaps.hp_expression_heap,
+			es_type_heaps = heaps.hp_type_heaps }, e_info, { cs & cs_symbol_table = cs_symbol_table })
+
+checkExpression free_vars (PE_Case case_ident expr alts) e_input e_state e_info cs
+	# (pattern_expr, free_vars, e_state, e_info, cs) = checkExpression free_vars expr e_input e_state e_info cs
+	  (guards, _, pattern_variables, defaul, free_vars, e_state, e_info, cs) = check_guarded_expressions free_vars alts [] case_ident.id_name e_input e_state e_info cs
+	  (pattern_expr, binds, es_expr_heap) = bind_pattern_variables pattern_variables pattern_expr e_state.es_expr_heap
+	  (case_expr, es_expr_heap) = build_case guards defaul pattern_expr case_ident es_expr_heap
+	  (result_expr, es_expr_heap) = buildLetExpression [] binds case_expr NoPos es_expr_heap
+	= (result_expr, free_vars, { e_state & es_expr_heap = es_expr_heap }, e_info, cs)
+	
+where
+	check_guarded_expressions free_vars [g] pattern_variables case_name e_input=:{ei_expr_level} e_state e_info cs
+		# e_input = { e_input & ei_expr_level = inc ei_expr_level }
+		= check_guarded_expression free_vars g NoPattern NoPattern pattern_variables No case_name e_input e_state e_info cs 
+	check_guarded_expressions free_vars [g : gs] pattern_variables case_name e_input=:{ei_expr_level} e_state e_info cs
+		# e_input = { e_input & ei_expr_level = inc ei_expr_level }
+		  (gs, pattern_scheme, pattern_variables, defaul, free_vars, e_state, e_info, cs)
+		  	= check_guarded_expressions free_vars gs pattern_variables case_name e_input e_state e_info cs
+		= check_guarded_expression free_vars g gs pattern_scheme pattern_variables defaul case_name e_input e_state e_info cs 
+	check_guarded_expression free_vars {calt_pattern,calt_rhs={rhs_alts,rhs_locals}} patterns pattern_scheme pattern_variables defaul case_name 
+				e_input=:{ei_expr_level,ei_mod_index} e_state=:{es_fun_defs,es_var_heap} e_info cs
+		# (pattern, (var_env, array_patterns), {ps_fun_defs,ps_var_heap}, e_info, cs)
+				= checkPattern calt_pattern No { pi_def_level = ei_expr_level, pi_mod_index = ei_mod_index, pi_is_node_pattern = False } ([], [])
+					{ps_var_heap = es_var_heap, ps_fun_defs = es_fun_defs} e_info cs
+		  e_state = { e_state & es_var_heap = ps_var_heap, es_fun_defs = ps_fun_defs }
+		  (rhs_expr, free_vars, e_state, e_info, cs)
+		  		= checkRhs free_vars rhs_alts rhs_locals e_input e_state e_info cs
+		  (expr_with_array_selections, free_vars, e_state=:{es_dynamics,es_expr_heap,es_var_heap}, e_info, cs)
+				= addArraySelections array_patterns rhs_expr free_vars e_input e_state e_info cs
+		  cs_symbol_table = removeLocalIdentsFromSymbolTable ei_expr_level var_env cs.cs_symbol_table
+		  (guarded_expr, pattern_scheme, pattern_variables, defaul, es_var_heap, es_expr_heap, dynamics_in_patterns, cs)
+		  		= transform_pattern pattern patterns pattern_scheme pattern_variables defaul expr_with_array_selections case_name
+		  									es_var_heap es_expr_heap es_dynamics { cs & cs_symbol_table = cs_symbol_table }
+		= (guarded_expr, pattern_scheme, pattern_variables, defaul, free_vars,
+			{ e_state & es_var_heap = es_var_heap, es_expr_heap = es_expr_heap, es_dynamics = dynamics_in_patterns },
+				e_info, cs)
+
+	transform_pattern :: !AuxiliaryPattern !CasePatterns !CasePatterns !(Env Ident VarInfoPtr) !(Optional (!Optional FreeVar, !Expression)) !Expression
+			!String !*VarHeap !*ExpressionHeap ![DynamicPtr] !*CheckState
+				-> (!CasePatterns, !CasePatterns, !Env Ident VarInfoPtr, !Optional (!Optional FreeVar,!Expression), !*VarHeap, !*ExpressionHeap, ![DynamicPtr], !*CheckState)
+	transform_pattern (AP_Algebraic cons_symbol type_index args opt_var) patterns pattern_scheme pattern_variables defaul result_expr _ var_store expr_heap opt_dynamics cs
+		# (var_args, result_expr, _, var_store, expr_heap, opt_dynamics, cs) = convertSubPatterns args result_expr NoPos var_store expr_heap opt_dynamics cs
+		  type_symbol = { glob_module = cons_symbol.glob_module, glob_object = type_index}
+		  pattern = { ap_symbol = cons_symbol, ap_vars = var_args, ap_expr = result_expr, ap_position = NoPos}
+		  pattern_variables = cons_optional opt_var pattern_variables
+		= case pattern_scheme of
+			AlgebraicPatterns alg_type _
+				| type_symbol == alg_type
+					# alg_patterns = case patterns of
+							AlgebraicPatterns _ alg_patterns -> alg_patterns
+							NoPattern -> []
+					-> (AlgebraicPatterns type_symbol [pattern : alg_patterns], pattern_scheme, pattern_variables, defaul, var_store, expr_heap, opt_dynamics, cs)
+					-> (patterns, pattern_scheme, pattern_variables, defaul, var_store, expr_heap, opt_dynamics,
+								{ cs & cs_error = checkError cons_symbol.glob_object.ds_ident "incompatible types of patterns" cs.cs_error })
+			NoPattern
+				-> (AlgebraicPatterns type_symbol [pattern], AlgebraicPatterns type_symbol [], pattern_variables, defaul, var_store, expr_heap, opt_dynamics, cs)
+			_
+				-> (patterns, pattern_scheme, pattern_variables, defaul, var_store, expr_heap, opt_dynamics,
+						{ cs & cs_error = checkError cons_symbol.glob_object.ds_ident "illegal combination of patterns" cs.cs_error })
+	transform_pattern (AP_Basic basic_val opt_var) patterns pattern_scheme pattern_variables defaul result_expr _ var_store expr_heap opt_dynamics cs
+		# pattern = { bp_value = basic_val, bp_expr = result_expr, bp_position = NoPos}
+		  pattern_variables = cons_optional opt_var pattern_variables
+		  (type_symbol, cs) = typeOfBasicValue basic_val cs
+		= case pattern_scheme of
+			BasicPatterns basic_type _
+				| type_symbol == basic_type
+					# basic_patterns = case patterns of
+							BasicPatterns _ basic_patterns
+								-> basic_patterns
+							NoPattern
+								-> [] 
+					-> (BasicPatterns basic_type [pattern : basic_patterns], pattern_scheme, pattern_variables, defaul, var_store, expr_heap, opt_dynamics, cs)
+					-> (patterns, pattern_scheme, pattern_variables, defaul, var_store, expr_heap, opt_dynamics,
+							{ cs & cs_error = checkError basic_val "incompatible types of patterns" cs.cs_error })
+			NoPattern
+				-> (BasicPatterns type_symbol [pattern], BasicPatterns type_symbol [], pattern_variables, defaul, var_store, expr_heap, opt_dynamics, cs)
+			_
+				-> (patterns, pattern_scheme, pattern_variables, defaul, var_store, expr_heap, opt_dynamics,
+						{ cs & cs_error = checkError basic_val "illegal combination of patterns" cs.cs_error})
+	transform_pattern (AP_Dynamic pattern type opt_var) patterns pattern_scheme pattern_variables defaul result_expr _ var_store expr_heap opt_dynamics cs
+		# (var_arg, result_expr, _, var_store, expr_heap, opt_dynamics, cs) = convertSubPattern pattern result_expr NoPos var_store expr_heap opt_dynamics cs
+		  (dynamic_info_ptr, expr_heap) = newPtr (EI_DynamicType type opt_dynamics) expr_heap
+		  pattern = { dp_var = var_arg, dp_type	= dynamic_info_ptr,	dp_rhs = result_expr, dp_type_patterns_vars = [],
+		  				dp_type_code = TCE_Empty, dp_position = NoPos }
+		  pattern_variables = cons_optional opt_var pattern_variables
+		= case pattern_scheme of
+			DynamicPatterns _
+				# dyn_patterns = case patterns of 
+										DynamicPatterns dyn_patterns
+											-> dyn_patterns
+										NoPattern
+											-> []
+				-> (DynamicPatterns [pattern : dyn_patterns], pattern_scheme, pattern_variables, defaul, var_store, expr_heap, [dynamic_info_ptr], cs)
+			NoPattern
+				-> (DynamicPatterns [pattern], DynamicPatterns [], pattern_variables, defaul, var_store, expr_heap, [dynamic_info_ptr], cs)
+			_
+				-> (patterns, pattern_scheme, pattern_variables, defaul, var_store, expr_heap, opt_dynamics,
+						{ cs & cs_error = checkError "<dynamic pattern>" "illegal combination of patterns" cs.cs_error })
+	transform_pattern (AP_Variable name var_info opt_var) NoPattern pattern_scheme pattern_variables No result_expr _ var_store expr_heap opt_dynamics cs
+		= ( NoPattern, pattern_scheme, cons_optional opt_var pattern_variables, 
+		  	Yes (Yes { fv_name = name, fv_info_ptr = var_info, fv_def_level = NotALevel, fv_count = 0 }, result_expr),
+			var_store, expr_heap, opt_dynamics, cs)		
+	transform_pattern (AP_Variable name var_info opt_var) patterns pattern_scheme pattern_variables defaul result_expr case_name var_store expr_heap opt_dynamics cs
+		# free_var = { fv_name = name, fv_info_ptr = var_info, fv_def_level = NotALevel, fv_count = 0 }
+		  (new_bound_var, expr_heap) = allocate_bound_var free_var expr_heap
+		  case_ident = { id_name = case_name, id_info = nilPtr }
+		  (new_case, expr_heap) = build_case patterns defaul (Var new_bound_var) case_ident expr_heap
+		  new_defaul = insert_as_default new_case result_expr
+		= (NoPattern, pattern_scheme, (cons_optional opt_var pattern_variables), Yes (Yes free_var, new_defaul),
+			var_store, expr_heap, opt_dynamics, cs)
+	transform_pattern (AP_WildCard (Yes opt_var)) patterns pattern_scheme pattern_variables defaul result_expr case_name var_store expr_heap opt_dynamics cs
+		= transform_pattern (AP_Variable opt_var.bind_src opt_var.bind_dst No) patterns pattern_scheme pattern_variables defaul
+							result_expr case_name var_store expr_heap opt_dynamics cs
+	transform_pattern (AP_WildCard no) NoPattern pattern_scheme pattern_variables No result_expr _ var_store expr_heap opt_dynamics cs
+		= (NoPattern, pattern_scheme, pattern_variables, Yes (No, result_expr), var_store, expr_heap, opt_dynamics, cs)
+	transform_pattern (AP_WildCard _) patterns pattern_scheme pattern_variables defaul result_expr case_name var_store expr_heap opt_dynamics cs
+		# (new_info_ptr, var_store) = newPtr VI_Empty var_store
+		= transform_pattern (AP_Variable (newVarId "wc") new_info_ptr No) patterns pattern_scheme pattern_variables defaul
+							result_expr case_name var_store expr_heap opt_dynamics cs
+	transform_pattern (AP_Empty name) patterns pattern_scheme pattern_variables defaul result_expr _ var_store expr_heap opt_dynamics cs
+		= (patterns, pattern_scheme, pattern_variables, defaul, var_store, expr_heap, opt_dynamics, cs)
+
+
+	insert_as_default :: !Expression !Expression -> Expression
+	insert_as_default to_insert (Let lad=:{let_expr})
+		= Let { lad & let_expr = insert_as_default to_insert let_expr }
+	insert_as_default to_insert (Case kees=:{case_default})
+		= case case_default of
+			No			-> Case { kees & case_default = Yes to_insert }
+			Yes defaul	-> Case { kees & case_default = Yes (insert_as_default to_insert defaul)}
+	insert_as_default _ expr = expr // checkWarning "pattern won't match"
+
+	build_case NoPattern defaul expr case_ident expr_heap
+		= case defaul of
+			Yes (opt_var, result)
+				-> case opt_var of
+					Yes var
+						# (let_expression, expr_heap) = bind_default_variable expr var result expr_heap
+						-> (let_expression, expr_heap)
+					No
+						-> (result, expr_heap)
+			No
+				-> (EE, expr_heap)
+	build_case (DynamicPatterns patterns) defaul expr case_ident expr_heap
+		= case defaul of
+			Yes (opt_var, result)
+				-> case opt_var of
+					Yes var
+						# (type_case_info_ptr, expr_heap) = newPtr EI_Empty expr_heap
+						  (bound_var, expr_heap) = allocate_bound_var var expr_heap
+						  result = buildTypeCase (Var bound_var) patterns (Yes result) type_case_info_ptr
+						  (case_expression, expr_heap) = bind_default_variable expr var result expr_heap
+					 	-> (case_expression, expr_heap)
+					No
+						# (type_case_info_ptr, expr_heap) = newPtr EI_Empty expr_heap
+						-> (buildTypeCase expr patterns (Yes result) type_case_info_ptr, expr_heap)
+			No
+				# (type_case_info_ptr, expr_heap) = newPtr EI_Empty expr_heap
+				-> (buildTypeCase expr patterns No type_case_info_ptr, expr_heap)
+	build_case patterns (Yes (opt_var,result)) expr case_ident expr_heap
+		= case opt_var of
+			Yes var
+				# (case_expr_ptr, expr_heap) = newPtr EI_Empty expr_heap
+				  (bound_var, expr_heap) = allocate_bound_var var expr_heap
+				  result = Case {case_expr = Var bound_var, case_guards = patterns, case_default = Yes result,
+								 case_ident = Yes case_ident, case_info_ptr = case_expr_ptr,
+								 case_default_pos = NoPos }
+				  (case_expression, expr_heap) = bind_default_variable expr var result expr_heap
+				-> (case_expression, expr_heap)
+			No
+				#  (case_expr_ptr, expr_heap) = newPtr EI_Empty expr_heap
+				-> (Case {case_expr = expr, case_guards = patterns, case_default = Yes result,
+						case_ident = Yes case_ident, case_info_ptr = case_expr_ptr, case_default_pos = NoPos }, expr_heap)
+	build_case patterns No expr case_ident expr_heap
+		# (case_expr_ptr, expr_heap) = newPtr EI_Empty expr_heap
+		= (Case {case_expr = expr, case_guards = patterns, case_default = No, case_ident = Yes case_ident,
+			case_info_ptr = case_expr_ptr, case_default_pos = NoPos }, expr_heap)
+
+	bind_default_variable lb_src lb_dst result_expr expr_heap
+		#  (let_expr_ptr, expr_heap) = newPtr EI_Empty expr_heap
+		= (Let {let_strict_binds = [], let_lazy_binds = [{ lb_src = lb_src, lb_dst = lb_dst, lb_position = NoPos }],
+				let_expr = result_expr, let_info_ptr = let_expr_ptr, let_expr_position = NoPos }, expr_heap)
+
+	bind_pattern_variables [] pattern_expr expr_heap
+		= (pattern_expr, [], expr_heap)
+	bind_pattern_variables [{bind_src,bind_dst} : variables] this_pattern_expr expr_heap
+		# free_var = { fv_name = bind_src, fv_info_ptr = bind_dst, fv_def_level = NotALevel, fv_count = 0 }
+		  (bound_var, expr_heap) = allocate_bound_var free_var expr_heap
+		  (pattern_expr, binds, expr_heap) = bind_pattern_variables variables (Var bound_var) expr_heap
+		= (pattern_expr, [{lb_src = this_pattern_expr, lb_dst = free_var, lb_position = NoPos } : binds], expr_heap)
+
+	cons_optional (Yes var) variables
+		= [ var : variables ]
+	cons_optional No variables
+		= variables
+
+checkExpression free_vars (PE_Selection is_unique expr [PS_Array index_expr]) e_input e_state e_info cs	
+	# (expr, free_vars, e_state, e_info, cs) = checkExpression free_vars expr e_input e_state e_info cs
+	| is_unique
+		# (glob_select_symb, cs) = getPredefinedGlobalSymbol PD_UnqArraySelectFun PD_StdArray STE_Member 2 cs
+		  (selector, free_vars, e_state, e_info, cs) = checkArraySelection glob_select_symb free_vars index_expr e_input e_state e_info cs
+		= (Selection No expr [selector], free_vars, e_state, e_info, cs)
+		# (glob_select_symb, cs) = getPredefinedGlobalSymbol PD_ArraySelectFun PD_StdArray STE_Member 2 cs
+		  (selector, free_vars, e_state, e_info, cs) = checkArraySelection glob_select_symb free_vars index_expr e_input e_state e_info cs
+		= (Selection No expr [selector], free_vars, e_state, e_info, cs)
+checkExpression free_vars (PE_Selection is_unique expr selectors) e_input e_state e_info cs	
+	# (selectors, free_vars, e_state, e_info, cs) = checkSelectors cEndWithSelection free_vars selectors e_input e_state e_info cs
+	  (expr, free_vars, e_state, e_info, cs) = checkExpression free_vars expr e_input e_state e_info cs
+	| is_unique
+		# (tuple_type, cs) = getPredefinedGlobalSymbol (GetTupleTypeIndex 2) PD_PredefinedModule STE_Type 2 cs
+		= (Selection (Yes tuple_type) expr selectors, free_vars, e_state, e_info, cs)
+		= (Selection No expr selectors, free_vars, e_state, e_info, cs)
+checkExpression free_vars (PE_Update expr1 selectors expr2) e_input e_state e_info cs	
+	# (expr1, free_vars, e_state, e_info, cs) = checkExpression free_vars expr1 e_input e_state e_info cs
+	  (selectors, free_vars, e_state, e_info, cs) = checkSelectors cEndWithUpdate free_vars selectors e_input e_state e_info cs
+	  (expr2, free_vars, e_state, e_info, cs) = checkExpression free_vars expr2 e_input e_state e_info cs
+	= (Update expr1 selectors expr2, free_vars, e_state, e_info, cs)
+checkExpression free_vars (PE_Tuple exprs) e_input e_state e_info cs
+	# (exprs, arity, free_vars, e_state, e_info, cs) = check_expression_list free_vars exprs e_input e_state e_info cs
+	  ({glob_object={ds_ident,ds_index, ds_arity},glob_module}, cs)
+	  		= getPredefinedGlobalSymbol (GetTupleConsIndex arity) PD_PredefinedModule STE_Constructor arity cs
+	= (App { app_symb = { symb_name = ds_ident, symb_arity = ds_arity,
+						  symb_kind = SK_Constructor { glob_object = ds_index, glob_module = glob_module }},
+			 app_args = exprs, app_info_ptr = nilPtr }, free_vars, e_state, e_info, cs)
+where
+	check_expression_list free_vars [] e_input e_state e_info cs
+		= ([], 0, free_vars, e_state, e_info, cs)
+	check_expression_list free_vars [expr : exprs] e_input e_state e_info cs
+		# (expr, free_vars, e_state, e_info, cs) = checkExpression free_vars expr e_input e_state e_info cs
+		  (exprs, length, free_vars, e_state, e_info, cs) = check_expression_list free_vars exprs e_input e_state e_info cs
+		= ([expr : exprs], inc length, free_vars, e_state, e_info, cs)
+
+checkExpression free_vars rec=:(PE_Record record opt_type fields) e_input=:{ei_expr_level,ei_mod_index} e_state e_info cs
+	# (opt_record_and_fields, e_info, cs) = checkFields ei_mod_index fields opt_type e_info cs
+	= case opt_record_and_fields of
+		Yes (cons=:{glob_module, glob_object}, _, new_fields)
+			# {ds_ident,ds_index,ds_arity} = glob_object
+			  rec_cons = { symb_name = ds_ident, symb_kind = SK_Constructor { glob_object = ds_index, glob_module = glob_module }, symb_arity = ds_arity }
+			-> case record of
+				PE_Empty
+					# (exprs, free_vars, e_state, e_info, cs) = check_field_exprs free_vars new_fields 0 RK_Constructor e_input e_state e_info cs
+					-> (App { app_symb = rec_cons, app_args = remove_fields exprs, app_info_ptr = nilPtr }, free_vars, e_state, e_info, cs)
+				_
+					# (rec_expr, free_vars, e_state, e_info, cs) = checkExpression free_vars record e_input e_state e_info cs
+					-> case rec_expr of
+						Var {var_info_ptr,var_name}
+							# (var_info, es_var_heap) = readPtr var_info_ptr e_state.es_var_heap
+							  e_state = { e_state & es_var_heap = es_var_heap }
+							-> case var_info of
+								VI_Record fields
+									# (exprs, free_vars, e_state, e_info, cs) 
+											= check_field_exprs free_vars new_fields 0 (RK_UpdateToConstructor fields) e_input e_state e_info cs
+									-> (App { app_symb = rec_cons, app_args = remove_fields exprs, app_info_ptr = nilPtr }, free_vars, e_state, e_info, cs)
+								_ 
+									# (exprs, free_vars, e_state, e_info, cs)
+											= check_field_exprs free_vars new_fields 0 RK_Update e_input e_state e_info cs
+									-> (RecordUpdate cons rec_expr exprs, free_vars, e_state, e_info, cs)
+						_ 
+							# (exprs, free_vars, e_state, e_info, cs)
+									= check_field_exprs free_vars new_fields 0 RK_Update e_input e_state e_info cs
+							-> (RecordUpdate cons rec_expr exprs, free_vars, e_state, e_info, cs)
+		No
+			-> (EE, free_vars, e_state, e_info, cs)
+where
+	remove_fields binds = [ bind_src \\ {bind_src} <- binds ]
+
+	check_field_exprs :: [FreeVar] [Bind ParsedExpr (Global FieldSymbol)] Int RecordKind ExpressionInput !*ExpressionState !*ExpressionInfo !*CheckState -> *(![.Bind Expression (Global FieldSymbol)],![FreeVar],!*ExpressionState,!*ExpressionInfo,!*CheckState);
+	check_field_exprs free_vars [] field_nr record_kind e_input e_state e_info cs
+		= ([], free_vars, e_state, e_info, cs)
+	check_field_exprs free_vars [field_expr : field_exprs] field_nr record_kind e_input e_state e_info cs
+		# (expr, free_vars, e_state, e_info, cs)
+			= check_field_expr free_vars field_expr field_nr record_kind e_input e_state e_info cs
+		  (exprs, free_vars, e_state, e_info, cs) = check_field_exprs free_vars field_exprs (inc field_nr) record_kind e_input e_state e_info cs
+		= ([expr : exprs], free_vars, e_state, e_info, cs)
+
+	check_field_expr :: [FreeVar] (Bind ParsedExpr (Global FieldSymbol)) Int RecordKind ExpressionInput *ExpressionState *ExpressionInfo *CheckState -> *(!.Bind Expression (Global FieldSymbol),![FreeVar],!*ExpressionState,!*ExpressionInfo,!*CheckState);
+	check_field_expr free_vars field=:{bind_src = PE_Empty, bind_dst={glob_object={fs_var,fs_name,fs_index},glob_module}} field_nr record_kind e_input e_state e_info cs
+		# (expr, free_vars, e_state, e_info, cs)
+			= checkIdentExpression cIsNotInExpressionList free_vars fs_var e_input e_state e_info cs
+		= ({ field & bind_src = expr }, free_vars, e_state, e_info, cs)
+	check_field_expr free_vars field=:{bind_src = PE_WildCard, bind_dst={glob_object=fs_name}} field_nr RK_Constructor e_input e_state e_info cs
+		= ({ field & bind_src = NoBind nilPtr }, free_vars, e_state, e_info, { cs & cs_error = checkError fs_name "field not specified" cs.cs_error })
+	check_field_expr free_vars field=:{bind_src = PE_WildCard} field_nr RK_Update e_input e_state=:{es_expr_heap} e_info cs
+		# (bind_expr_ptr, es_expr_heap) = newPtr EI_Empty es_expr_heap
+		= ({ field & bind_src = NoBind bind_expr_ptr }, free_vars, { e_state & es_expr_heap = es_expr_heap }, e_info, cs)
+	check_field_expr free_vars field=:{bind_src = PE_WildCard} field_nr (RK_UpdateToConstructor fields) e_input e_state=:{es_expr_heap} e_info cs
+		# (var_name, var_info_ptr) = get_field_var (fields !! field_nr)
+		  (var_expr_ptr, es_expr_heap) = newPtr EI_Empty es_expr_heap
+		= ({ field & bind_src = Var { var_name = var_name, var_info_ptr = var_info_ptr, var_expr_ptr = var_expr_ptr }}, free_vars,
+				{ e_state & es_expr_heap = es_expr_heap }, e_info, cs)
+	check_field_expr free_vars field=:{bind_src} field_nr upd_record e_input e_state e_info cs
+		# (expr, free_vars, e_state, e_info, cs)
+			= checkExpression free_vars bind_src e_input e_state e_info cs
+		= ({ field & bind_src = expr }, free_vars, e_state, e_info, cs)
+	
+	get_field_var (AP_Algebraic _ _ _ (Yes {bind_src,bind_dst}))
+		= (bind_src, bind_dst)
+	get_field_var (AP_Basic _ (Yes {bind_src,bind_dst}))
+		= (bind_src, bind_dst)
+	get_field_var (AP_Dynamic _ _ (Yes {bind_src,bind_dst}))
+		= (bind_src, bind_dst)
+	get_field_var (AP_Variable id var_ptr _)
+		= (id, var_ptr)
+	get_field_var (AP_WildCard (Yes {bind_src,bind_dst}))
+		= (bind_src, bind_dst)
+	get_field_var _
+		= ({ id_name = "** ERRONEOUS **", id_info = nilPtr }, nilPtr)
+
+checkExpression free_vars (PE_Dynamic expr opt_type) e_input e_state=:{es_expr_heap,es_dynamics} e_info cs=:{cs_x}
+	# (dyn_info_ptr, es_expr_heap) = newPtr (EI_Dynamic opt_type) es_expr_heap
+	  (dyn_expr, free_vars, e_state, e_info, cs) = checkExpression free_vars expr e_input
+	  		{e_state & es_dynamics = [dyn_info_ptr : es_dynamics], es_expr_heap = es_expr_heap } e_info cs
+	= (DynamicExpr { dyn_expr = dyn_expr, dyn_opt_type = opt_type, dyn_info_ptr = dyn_info_ptr, dyn_type_code = TCE_Empty, dyn_uni_vars = [] },
+			free_vars, e_state, e_info, { cs & cs_x.x_needed_modules = cs_x.x_needed_modules bitor cNeedStdDynamics }) 
+
+checkExpression free_vars (PE_Basic basic_value) e_input e_state e_info cs
+	# (basic_type, cs) = typeOfBasicValue basic_value cs
+	= (BasicExpr basic_value basic_type, free_vars, e_state, e_info, cs)
+
+checkExpression free_vars (PE_ABC_Code code_sequence do_inline) e_input e_state e_info cs
+	= (ABCCodeExpr code_sequence do_inline, free_vars, e_state, e_info, cs)
+checkExpression free_vars (PE_Any_Code ins outs code_sequence) e_input e_state e_info cs
+	# (ins, (free_vars, e_state, e_info, cs)) = check_in_parameters e_input ins (free_vars, e_state, e_info, cs)
+	  (new_outs, (e_state, cs)) = check_out_parameters e_input.ei_expr_level outs (e_state, cs)
+	  cs_symbol_table = remove_out_parameters_from_symbol_table e_input.ei_expr_level outs cs.cs_symbol_table
+	= (AnyCodeExpr ins new_outs code_sequence, free_vars, e_state, e_info, { cs & cs_symbol_table = cs_symbol_table })
+where
+	check_in_parameters e_input params fv_es_ei_cs
+		= mapSt (check_in_parameter e_input) params fv_es_ei_cs
+
+	check_in_parameter e_input { bind_src, bind_dst } (free_vars, e_state, e_info, cs)
+		# (id_expr, free_vars, e_state, e_info, cs) = checkIdentExpression cIsNotInExpressionList free_vars bind_dst e_input e_state e_info cs
+		= case id_expr of
+			Var var
+				-> ({ bind_dst = var, bind_src = bind_src }, (free_vars, e_state, e_info, cs))
+			_
+				-> ({ bind_dst = { var_name = bind_dst, var_info_ptr = nilPtr, var_expr_ptr = nilPtr }, bind_src = bind_src }, (free_vars, e_state, e_info,
+						{ cs & cs_error = checkError bind_src "bound variable expected" cs.cs_error }))
+
+	check_out_parameters expr_level params es_cs
+		= mapSt (check_out_parameter expr_level) params es_cs
+
+	check_out_parameter expr_level bind=:{ bind_src, bind_dst } (e_state, cs)
+		| isLowerCaseName bind_dst.id_name
+			# (entry, cs_symbol_table) = readPtr bind_dst.id_info cs.cs_symbol_table
+			# (new_info_ptr, es_var_heap) = newPtr VI_Empty e_state.es_var_heap
+			  cs = checkPatternVariable expr_level entry bind_dst new_info_ptr { cs & cs_symbol_table = cs_symbol_table }
+			= (	{ bind & bind_dst = { fv_def_level = expr_level, fv_name = bind_dst, fv_info_ptr = new_info_ptr, fv_count = 0 }},
+					( { e_state & es_var_heap = es_var_heap }, cs))
+			= ( { bind & bind_dst = { fv_def_level = expr_level, fv_name = bind_dst, fv_info_ptr = nilPtr, fv_count = 0 }},
+					( e_state, { cs & cs_error = checkError bind_src "variable expected" cs.cs_error }))
+
+	remove_out_parameters_from_symbol_table expr_level idents symbol_table
+		= foldSt (\{bind_dst} -> removeIdentFromSymbolTable expr_level bind_dst) idents symbol_table
+
+checkExpression free_vars (PE_Ident id) e_input e_state e_info cs
+	= checkIdentExpression cIsNotInExpressionList free_vars id e_input e_state e_info cs
+checkExpression free_vars expr e_input e_state e_info cs
+	= abort "checkExpression (check.icl, line 1433)" // <<- expr
+
+
+
+checkIdentExpression :: !Bool ![FreeVar] !Ident !ExpressionInput !*ExpressionState !u:ExpressionInfo !*CheckState
+	-> (!Expression, ![FreeVar], !*ExpressionState, !u:ExpressionInfo, !*CheckState)
+checkIdentExpression is_expr_list free_vars id=:{id_info} e_input e_state e_info cs=:{cs_symbol_table}
+	# (entry, cs_symbol_table) = readPtr id_info cs_symbol_table
+	= check_id_expression entry is_expr_list free_vars id e_input e_state e_info { cs & cs_symbol_table = cs_symbol_table }
+where
+	check_id_expression :: !SymbolTableEntry !Bool ![FreeVar] !Ident !ExpressionInput !*ExpressionState !u:ExpressionInfo !*CheckState
+		-> (!Expression, ![FreeVar], !*ExpressionState, !u:ExpressionInfo, !*CheckState)
+
+	check_id_expression {ste_kind = STE_Empty} is_expr_list free_vars id e_input e_state e_info cs=:{cs_error,cs_predef_symbols,cs_x}
+		# ({pds_ident=from_ident}) = cs_predef_symbols.[PD_From]
+		  ({pds_ident=from_then_ident}) = cs_predef_symbols.[PD_FromThen]
+		  ({pds_ident=from_to_ident}) = cs_predef_symbols.[PD_FromTo]
+		  ({pds_ident=from_then_to_ident}) = cs_predef_symbols.[PD_FromThenTo]
+		| id==from_ident || id==from_then_ident || id==from_to_ident || id==from_then_to_ident
+			= (EE, free_vars, e_state, e_info, { cs & cs_x.x_needed_modules = cs_x.x_needed_modules bitor cNeedStdEnum})
+				// instead of giving an error message remember that StdEnum should have been imported.
+				// Error will be given in function check_needed_modules_are_imported
+		# ({pds_ident=createArray_ident}) = cs_predef_symbols.[PD__CreateArrayFun]
+		  ({pds_ident=uselect_ident}) = cs_predef_symbols.[PD_UnqArraySelectFun]
+		  ({pds_ident=update_ident}) = cs_predef_symbols.[PD_ArrayUpdateFun]
+		  ({pds_ident=usize_ident}) = cs_predef_symbols.[PD_UnqArraySizeFun]
+		| id==createArray_ident || id==uselect_ident || id==update_ident || id==usize_ident
+			= (EE, free_vars, e_state, e_info, { cs & cs_x.x_needed_modules = cs_x.x_needed_modules bitor cNeedStdArray})
+				// instead of giving an error message remember that StdArray should have been be imported.
+				//  Error will be given in function check_needed_modules_are_imported
+		= (EE, free_vars, e_state, e_info, { cs & cs_error = checkError id "undefined" cs_error })
+	check_id_expression {ste_kind = STE_Variable info_ptr,ste_def_level} is_expr_list free_vars id e_input=:{ei_fun_level} e_state=:{es_expr_heap} e_info cs
+		| ste_def_level < ei_fun_level
+			# free_var = { fv_def_level = ste_def_level, fv_name = id, fv_info_ptr = info_ptr, fv_count = 0 }
+			  (free_var_added, free_vars) = newFreeVariable free_var free_vars
+			= (FreeVar free_var, free_vars, e_state, e_info, cs)
+			#! (var_expr_ptr, es_expr_heap) = newPtr EI_Empty es_expr_heap
+			= (Var {var_name = id, var_info_ptr = info_ptr, var_expr_ptr = var_expr_ptr}, free_vars,
+					{e_state & es_expr_heap = es_expr_heap}, e_info, cs)
+	check_id_expression entry is_expr_list free_vars id=:{id_info} e_input e_state e_info cs
+		# (symb_kind, arity, priority, is_a_function, e_state, e_info, cs) = determine_info_of_symbol entry id_info e_input e_state e_info cs
+		  symbol = { symb_name = id, symb_kind = symb_kind, symb_arity = 0 }
+  		| is_expr_list
+			= (Constant symbol arity priority is_a_function, free_vars, e_state, e_info, cs)
+			# (app_expr, e_state, cs_error) = buildApplication symbol arity 0 is_a_function [] e_state cs.cs_error
+			= (app_expr, free_vars, e_state, e_info, { cs & cs_error = cs_error })
+
+	determine_info_of_symbol :: !SymbolTableEntry !SymbolPtr !ExpressionInput !*ExpressionState !u:ExpressionInfo !*CheckState
+		-> (!SymbKind, !Int, !Priority, !Bool, !*ExpressionState, !u:ExpressionInfo,!*CheckState)
+	determine_info_of_symbol entry=:{ste_kind=STE_FunctionOrMacro calls,ste_index,ste_def_level} symb_info
+				e_input=:{ei_fun_index, ei_mod_index} e_state=:{es_fun_defs,es_calls} e_info=:{ef_is_macro_fun} cs=:{cs_symbol_table,cs_x}
+		# ({fun_symb,fun_arity,fun_kind,fun_priority}, es_fun_defs) = es_fun_defs![ste_index]
+		# index = { glob_object = ste_index, glob_module = cs_x.x_main_dcl_module_n }
+		| is_called_before ei_fun_index calls
+			| case fun_kind of FK_DefMacro->True ; FK_ImpMacro->True; _ -> False
+				= (SK_Macro index, fun_arity, fun_priority, cIsAFunction, { e_state & es_fun_defs = es_fun_defs }, e_info, cs)
+				# symbol_kind = if ef_is_macro_fun (SK_LocalMacroFunction ste_index) (SK_Function index)
+				= (symbol_kind, fun_arity, fun_priority, cIsAFunction, { e_state & es_fun_defs = es_fun_defs }, e_info, cs)
+			# cs = { cs & cs_symbol_table = cs_symbol_table <:= (symb_info, { entry & ste_kind = STE_FunctionOrMacro [ ei_fun_index : calls ]})}
+			  e_state = { e_state & es_fun_defs = es_fun_defs, es_calls = [{ fc_index = ste_index, fc_level = ste_def_level} : es_calls ]}
+			# symbol_kind = case fun_kind of
+				FK_DefMacro
+					-> SK_Macro index;
+				FK_ImpMacro
+					-> SK_Macro index;
+				_
+					| ef_is_macro_fun
+						-> SK_LocalMacroFunction ste_index
+						-> SK_Function index
+			= (symbol_kind, fun_arity, fun_priority, cIsAFunction, e_state, e_info, cs)
+	where
+		is_called_before caller_index []
+			= False
+		is_called_before caller_index [called_index : calls]
+			= caller_index == called_index || is_called_before caller_index calls
+
+	determine_info_of_symbol entry=:{ste_kind=STE_Imported kind mod_index,ste_index} symb_index e_input e_state e_info=:{ef_modules} cs
+		# (mod_def, ef_modules) = ef_modules![mod_index]
+		# (kind, arity, priotity, is_fun) = ste_kind_to_symbol_kind kind ste_index mod_index mod_def
+		= (kind, arity, priotity, is_fun, e_state, { e_info & ef_modules = ef_modules }, cs)
+	where
+		ste_kind_to_symbol_kind :: !STE_Kind !Index !Index !DclModule -> (!SymbKind, !Int, !Priority, !Bool);
+		ste_kind_to_symbol_kind STE_DclFunction def_index mod_index {dcl_functions,dcl_conversions}
+			# {ft_type={st_arity},ft_priority} = dcl_functions.[def_index]
+			# def_index = convertIndex def_index (toInt STE_DclFunction) dcl_conversions
+			= (SK_Function { glob_object = def_index, glob_module = mod_index }, st_arity, ft_priority, cIsAFunction)
+		ste_kind_to_symbol_kind STE_Member def_index mod_index {dcl_common={com_member_defs},dcl_conversions}
+			# {me_type={st_arity},me_priority} = com_member_defs.[def_index]
+			# def_index = convertIndex def_index (toInt STE_Member) dcl_conversions
+			= (SK_OverloadedFunction { glob_object = def_index, glob_module = mod_index }, st_arity, me_priority, cIsAFunction)
+		ste_kind_to_symbol_kind STE_Constructor def_index mod_index {dcl_common={com_cons_defs},dcl_conversions}
+			# {cons_type={st_arity},cons_priority} = com_cons_defs.[def_index]
+			# def_index = convertIndex def_index (toInt STE_Constructor) dcl_conversions
+			= (SK_Constructor { glob_object = def_index, glob_module = mod_index }, st_arity, cons_priority, cIsNotAFunction)
+
+	determine_info_of_symbol {ste_kind=STE_Member, ste_index} _ e_input=:{ei_mod_index} e_state e_info=:{ef_member_defs} cs
+		# ({me_type={st_arity},me_priority}, ef_member_defs) = ef_member_defs![ste_index]
+		= (SK_OverloadedFunction { glob_object = ste_index, glob_module = ei_mod_index}, st_arity, me_priority, cIsAFunction,
+				e_state, { e_info & ef_member_defs = ef_member_defs }, cs)
+	determine_info_of_symbol {ste_kind=STE_Constructor, ste_index} _ e_input=:{ei_mod_index} e_state e_info=:{ef_cons_defs} cs
+		# ({cons_type={st_arity},cons_priority}, ef_cons_defs) = ef_cons_defs![ste_index]
+		= (SK_Constructor { glob_object = ste_index, glob_module =  ei_mod_index}, st_arity, cons_priority, cIsNotAFunction,
+				e_state, { e_info & ef_cons_defs = ef_cons_defs }, cs)
+	determine_info_of_symbol {ste_kind=STE_DclFunction, ste_index} _ e_input=:{ei_mod_index} e_state e_info=:{ef_modules} cs
+		# (mod_def, ef_modules) = ef_modules![ei_mod_index]
+		# {ft_type={st_arity},ft_priority} = mod_def.dcl_functions.[ste_index]
+		  def_index = convertIndex ste_index (toInt STE_DclFunction) mod_def.dcl_conversions
+		= (SK_Function { glob_object = def_index, glob_module =  ei_mod_index}, st_arity, ft_priority, cIsAFunction,
+				e_state, { e_info & ef_modules = ef_modules }, cs)
+
+
+
+checkPattern :: !ParsedExpr !(Optional (Bind Ident VarInfoPtr)) !PatternInput !(![Ident], ![ArrayPattern]) !*PatternState !*ExpressionInfo !*CheckState
+									-> (!AuxiliaryPattern, !(![Ident], ![ArrayPattern]), !*PatternState, !*ExpressionInfo, !*CheckState)
+checkPattern (PE_List [exp]) opt_var p_input accus ps e_info cs=:{cs_symbol_table}
+	= case exp of
+		PE_Ident ident
+			-> checkIdentPattern cIsNotInExpressionList ident opt_var p_input accus ps e_info cs
+		_
+			-> checkPattern exp opt_var p_input accus ps e_info cs
+
+checkPattern (PE_List [exp1, exp2 : exps]) opt_var p_input accus ps e_info cs
+	# (exp_pat, accus, ps, e_info, cs) = check_pattern exp1 p_input accus ps e_info cs
+	= check_patterns [exp_pat] exp2 exps opt_var p_input accus ps e_info cs
+	where
+		check_patterns left middle [] opt_var p_input=:{pi_mod_index} accus ps e_info cs
+			# (mid_pat, accus, ps, e_info, cs) = checkPattern middle No p_input accus ps e_info cs
+			  (pat, ps, e_info, cs) = combine_patterns pi_mod_index opt_var [mid_pat : left] [] 0 ps e_info cs
+			= (pat, accus, ps, e_info, cs)
+		check_patterns left middle [right:rest] opt_var p_input=:{pi_mod_index} accus ps e_info cs
+			# (mid_pat, accus, ps, e_info, cs) = check_pattern middle p_input accus ps e_info cs
+			= case mid_pat of
+				AP_Constant kind constant=:{glob_object={ds_arity,ds_ident}} prio
+					| ds_arity == 0
+						# (pattern, ps, e_info, cs) = buildPattern pi_mod_index kind constant [] No ps e_info cs
+						-> check_patterns [pattern: left] right rest opt_var p_input accus ps e_info cs
+					| is_infix_constructor prio
+						# (left_arg, ps, e_info, cs) = combine_patterns pi_mod_index No left [] 0 ps e_info cs
+						  (right_pat, accus, ps, e_info, cs) = check_pattern right p_input accus ps e_info cs
+						-> check_infix_pattern [] left_arg kind constant prio [right_pat] rest
+									opt_var p_input accus ps e_info cs
+						-> (AP_Empty ds_ident, accus, ps, e_info,
+								{ cs & cs_error = checkError ds_ident "arguments of constructor are missing" cs.cs_error })
+				_
+					-> check_patterns [mid_pat : left] right rest opt_var p_input accus ps e_info cs
+
+		check_pattern (PE_Ident id) p_input accus ps e_info cs
+			= checkIdentPattern cIsInExpressionList id No p_input accus ps e_info cs
+		check_pattern expr p_input accus ps e_info cs
+			= checkPattern expr No p_input accus ps e_info cs
+		
+	 	check_infix_pattern left_args left kind cons prio middle [] opt_var p_input=:{pi_mod_index} accus ps e_info cs
+			# (middle_pat, ps, e_info, cs) = combine_patterns pi_mod_index No middle [] 0 ps e_info cs
+			  (pattern, ps, e_info, cs) = buildPattern pi_mod_index kind cons [left,middle_pat] opt_var ps e_info cs
+			  (pattern, ps, e_info, cs) = build_final_pattern pi_mod_index left_args pattern ps e_info cs
+			= (pattern, accus, ps, e_info, cs)
+	 	check_infix_pattern left_args left kind cons prio middle [right] opt_var  p_input=:{pi_mod_index} accus ps e_info cs
+			# (right_pat, accus, ps, e_info, cs) = checkPattern right No p_input accus ps e_info cs
+			  (right_arg, ps, e_info, cs) = combine_patterns pi_mod_index No [right_pat : middle] [] 0 ps e_info cs
+			  (pattern, ps, e_info, cs) = buildPattern pi_mod_index kind cons [left,right_arg] opt_var ps e_info cs
+			  (pattern, ps, e_info, cs) = build_final_pattern pi_mod_index left_args pattern ps e_info cs
+			= (pattern, accus, ps, e_info, cs)
+	 	check_infix_pattern left_args left kind1 cons1 prio1 middle [inf_cons, arg : rest] opt_var p_input=:{pi_mod_index} accus ps e_info cs
+			# (inf_cons_pat, accus, ps, e_info, cs) = check_pattern inf_cons p_input accus ps e_info cs
+			= case inf_cons_pat of
+				AP_Constant kind2 cons2=:{glob_object={ds_ident,ds_arity}} prio2
+					| ds_arity == 0
+						# (middle_pat, ps, e_info, cs) = combine_patterns pi_mod_index No middle [] 0 ps e_info cs
+						  (pattern2, ps, e_info, cs) = buildPattern pi_mod_index kind2 cons2 [] No ps e_info cs
+						  (pattern1, ps, e_info, cs) = buildPattern pi_mod_index kind1 cons1 [left,middle_pat] No ps e_info cs
+						  (pattern1, ps, e_info, cs) = build_final_pattern pi_mod_index left_args pattern1 ps e_info cs
+						-> check_patterns [pattern2,pattern1] arg rest opt_var p_input accus ps e_info cs
+					| is_infix_constructor prio2
+						# optional_prio = determinePriority prio1 prio2
+						-> case optional_prio of
+							Yes priority
+								# (arg_pat, accus, ps, e_info, cs) = check_pattern arg p_input accus ps e_info cs
+								| priority
+									# (middle_pat, ps, e_info, cs) = combine_patterns pi_mod_index No middle [] 0 ps e_info cs
+								      (pattern, ps, e_info, cs) = buildPattern pi_mod_index kind1 cons1 [left,middle_pat] No ps e_info cs
+								      (left_args, pattern, ps, e_info, cs) = build_left_pattern pi_mod_index left_args prio2 pattern ps e_info cs
+									-> check_infix_pattern left_args pattern kind2 cons2 prio2 [arg_pat] rest opt_var p_input accus ps e_info cs 
+									# (middle_pat, ps, e_info, cs) = combine_patterns pi_mod_index No middle [] 0 ps e_info cs
+									-> check_infix_pattern [(kind1, cons1, prio1, left) : left_args]
+									  				middle_pat kind2 cons2 prio2 [arg_pat] rest No p_input accus ps e_info cs
+							No
+								-> (AP_Empty ds_ident, accus, ps, e_info, { cs & cs_error = checkError ds_ident "conflicting priorities" cs.cs_error })
+						-> (AP_Empty ds_ident, accus, ps, e_info, { cs & cs_error = checkError ds_ident "arguments of constructor are missing" cs.cs_error })
+				_
+					-> check_infix_pattern left_args left kind1 cons1 prio1 [inf_cons_pat : middle] [arg : rest] opt_var p_input accus ps e_info cs 
+
+		is_infix_constructor (Prio _ _) = True
+		is_infix_constructor _ = False
+
+		build_left_pattern mod_index [] _ result_pattern ps e_info cs
+			= ([], result_pattern, ps, e_info, cs)		
+		build_left_pattern mod_index la=:[(kind, cons, priol, left) : left_args] prior result_pattern ps e_info cs
+			# optional_prio = determinePriority priol prior
+			= case optional_prio of
+				Yes priority
+					| priority
+						# (result_pattern,  ps, e_info, cs) = buildPattern mod_index kind cons [left,result_pattern] No ps e_info cs
+						-> build_left_pattern mod_index left_args prior result_pattern ps e_info cs
+						-> (la, result_pattern,  ps, e_info, cs)
+				No
+					-> (la, result_pattern,  ps, e_info,{ cs & cs_error = checkError cons.glob_object.ds_ident "conflicting priorities" cs.cs_error })
+
+		build_final_pattern mod_index [] result_pattern ps e_info cs
+			= (result_pattern,  ps, e_info, cs)		
+		build_final_pattern mod_index [(kind, cons, priol, left) : left_appls] result_pattern ps e_info cs
+			# (result_pattern, ps, e_info, cs) = buildPattern mod_index kind cons [left,result_pattern] No ps e_info cs
+			= build_final_pattern mod_index left_appls result_pattern ps e_info cs
+
+		combine_patterns mod_index opt_var [first_expr] args nr_of_args ps e_info cs
+			= case first_expr of
+				AP_Constant kind constant=:{glob_object={ds_ident,ds_arity}} _
+					| ds_arity == nr_of_args
+						# (pattern, ps, e_info, cs) = buildPattern mod_index kind constant args opt_var ps e_info cs
+						-> (pattern, ps, e_info, cs)
+						-> (AP_Empty ds_ident, ps, e_info, { cs & cs_error = checkError ds_ident "used with wrong arity" cs.cs_error})
+				_
+					| nr_of_args == 0
+						-> (first_expr, ps, e_info, cs)
+						-> (first_expr, ps, e_info, { cs & cs_error = checkError "<pattern>" "(curried) application not allowed " cs.cs_error })
+		combine_patterns mod_index opt_var [rev_arg : rev_args] args arity ps e_info cs
+			= combine_patterns mod_index opt_var rev_args [rev_arg : args] (inc arity) ps e_info cs
+/*
+		combine_optional_variables (Yes var1) (Yes var2) error
+			= (Yes var1, checkError var2.bind_dst "pattern already bound" error)
+		combine_optional_variables No opt_var error
+			= (opt_var, error)
+		combine_optional_variables opt_var _ error
+			= (opt_var, error)
+*/
+
+checkPattern (PE_DynamicPattern pattern type) opt_var p_input accus ps e_info cs=:{cs_x}
+	# (dyn_pat, accus, ps, e_info, cs) = checkPattern pattern No p_input accus ps e_info cs
+	= (AP_Dynamic dyn_pat type opt_var, accus, ps, e_info, { cs & cs_x.x_needed_modules = cs_x.x_needed_modules bitor cNeedStdDynamics })
+
+checkPattern (PE_Basic basic_value) opt_var p_input accus ps e_info cs
+	= (AP_Basic basic_value opt_var, accus, ps, e_info, cs)
+
+checkPattern (PE_Tuple tuple_args) opt_var p_input accus ps e_info cs
+	# (patterns, arity, accus, ps, e_info, cs) = check_tuple_patterns tuple_args p_input accus ps e_info cs
+	  (tuple_symbol, cs) = getPredefinedGlobalSymbol (GetTupleConsIndex arity) PD_PredefinedModule STE_Constructor arity cs
+	# ({cons_type_index}, e_info) = e_info!ef_modules.[tuple_symbol.glob_module].dcl_common.com_cons_defs.[tuple_symbol.glob_object.ds_index]
+	= (AP_Algebraic tuple_symbol cons_type_index patterns opt_var, accus, ps, e_info, cs)
+where
+	check_tuple_patterns [] p_input accus ps e_info cs
+		= ([], 0, accus, ps, e_info, cs)
+	check_tuple_patterns [expr : exprs] p_input accus ps e_info cs
+		# (pattern, accus, ps, e_info, cs) = checkPattern expr No p_input accus ps e_info cs
+		  (patterns, length, accus, ps, e_info, cs) = check_tuple_patterns exprs p_input accus ps e_info cs
+		= ([pattern : patterns], inc length, accus, ps, e_info, cs)
+checkPattern (PE_Record record opt_type fields) opt_var p_input=:{pi_mod_index, pi_is_node_pattern} accus=:(var_env, array_patterns) ps e_info cs
+	# (opt_record_and_fields, e_info, cs) = checkFields pi_mod_index fields opt_type e_info cs
+	= case opt_record_and_fields of
+		Yes (record_symbol, type_index, new_fields)
+			# (patterns, (var_env, array_patterns, ps, e_info, cs)) = mapSt (check_field_pattern p_input) new_fields (var_env, array_patterns, ps, e_info, cs)
+			  (patterns, ps_var_heap) = bind_opt_record_variable opt_var pi_is_node_pattern patterns new_fields ps.ps_var_heap
+			-> (AP_Algebraic record_symbol type_index patterns opt_var, (var_env, array_patterns), { ps & ps_var_heap = ps_var_heap }, e_info, cs)
+		No
+			-> (AP_Empty (hd fields).bind_dst, accus, ps, e_info, cs)
+where
+
+	check_field_pattern p_input=:{pi_def_level} {bind_src = PE_Empty, bind_dst = {glob_object={fs_var}}} 
+						(var_env, array_patterns, ps, e_info, cs)
+		# (entry, cs_symbol_table) = readPtr fs_var.id_info cs.cs_symbol_table
+		# (new_info_ptr, ps_var_heap) = newPtr VI_Empty ps.ps_var_heap
+		  cs = checkPatternVariable pi_def_level entry fs_var new_info_ptr { cs & cs_symbol_table = cs_symbol_table }
+		= (AP_Variable fs_var new_info_ptr No, ([ fs_var : var_env ], array_patterns, { ps & ps_var_heap = ps_var_heap }, e_info, cs))
+	check_field_pattern p_input {bind_src = PE_WildCard, bind_dst={glob_object={fs_var}}} (var_env, array_patterns, ps, e_info, cs)
+		# (new_info_ptr, ps_var_heap) = newPtr VI_Empty ps.ps_var_heap
+		= (AP_WildCard (Yes { bind_src = fs_var, bind_dst = new_info_ptr}), (var_env, array_patterns, { ps & ps_var_heap = ps_var_heap }, e_info, cs))
+	check_field_pattern p_input {bind_src,bind_dst} (var_env, array_patterns, ps, e_info, cs)
+		# (pattern, (var_env, array_patterns), ps, e_info, cs) = checkPattern bind_src No p_input (var_env, array_patterns) ps e_info cs
+		= (pattern, (var_env, array_patterns, ps, e_info, cs))
+
+
+	add_bound_variable (AP_Algebraic symbol index patterns No) {bind_dst = {glob_object={fs_var}}} ps_var_heap
+		# (new_info_ptr, ps_var_heap) = newPtr VI_Empty ps_var_heap
+		= (AP_Algebraic symbol index patterns (Yes { bind_src = fs_var, bind_dst = new_info_ptr}), ps_var_heap)
+	add_bound_variable (AP_Basic bas_val No) {bind_dst = {glob_object={fs_var}}} ps_var_heap
+		# (new_info_ptr, ps_var_heap) = newPtr VI_Empty ps_var_heap
+		= (AP_Basic bas_val (Yes { bind_src = fs_var, bind_dst = new_info_ptr}), ps_var_heap)
+	add_bound_variable (AP_Dynamic dynamic_pattern dynamic_type No) {bind_dst = {glob_object={fs_var}}} ps_var_heap
+		# (new_info_ptr, ps_var_heap) = newPtr VI_Empty ps_var_heap
+		= (AP_Dynamic dynamic_pattern dynamic_type (Yes { bind_src = fs_var, bind_dst = new_info_ptr}), ps_var_heap)
+	add_bound_variable pattern _ ps_var_heap
+		= (pattern, ps_var_heap)
+
+	add_bound_variables [] _ var_heap
+		= ([] , var_heap)
+	add_bound_variables [ap : aps] [field : fields] var_heap
+		# (ap, var_heap) = add_bound_variable ap field var_heap
+		  (aps, var_heap) = add_bound_variables aps fields var_heap
+		= ([ap : aps], var_heap)
+
+	bind_opt_record_variable (Yes {bind_dst}) False patterns fields var_heap
+		# (patterns, var_heap) = add_bound_variables patterns fields var_heap
+		= (patterns, var_heap <:= (bind_dst, VI_Record patterns))
+	bind_opt_record_variable no is_node_pattern patterns _ var_heap
+		= (patterns, var_heap)
+
+checkPattern (PE_Bound bind) opt_var p_input accus ps e_info cs
+	= checkBoundPattern bind opt_var p_input accus ps e_info cs
+checkPattern (PE_Ident id) opt_var p_input accus ps e_info cs
+	= checkIdentPattern cIsNotInExpressionList id opt_var p_input accus ps e_info cs
+checkPattern PE_WildCard opt_var p_input accus ps e_info cs
+	= (AP_WildCard No, accus, ps, e_info, cs)
+checkPattern (PE_ArrayPattern selections) opt_var p_input (var_env, array_patterns) ps e_info cs
+	# (var_env, ap_selections, ps_var_heap, cs)
+			= foldSt (check_array_selection p_input.pi_def_level) selections (var_env, [], ps.ps_var_heap, cs)
+	  array_var_ident = case opt_var of 
+	  						Yes {bind_src}
+	  							-> bind_src
+	  						No
+	  							-> { id_name = "_a", id_info = nilPtr }
+	  (array_var, ps_var_heap) = allocate_free_var array_var_ident ps_var_heap
+	= (AP_Variable array_var_ident array_var.fv_info_ptr No, 
+		(var_env, [{ ap_opt_var = opt_var, ap_array_var = array_var, ap_selections = ap_selections } :array_patterns]),
+		{ ps & ps_var_heap = ps_var_heap }, e_info, cs)
+  where
+	check_array_selection def_level bind=:{bind_dst} states
+		= check_rhs def_level bind (foldSt check_index_expr bind_dst states)
+		
+	check_index_expr (PE_Ident {id_name}) states
+		| isLowerCaseName id_name
+			= states
+		// further with next alternative
+	check_index_expr (PE_Basic (BVI _)) states
+			= states
+	check_index_expr _ (var_env, ap_selections, var_heap, cs)
+		= (var_env, ap_selections, var_heap, { cs & cs_error = checkError "" "variable or integer constant expected as index expression" cs.cs_error })
+
+	check_rhs def_level {bind_src=PE_Ident ident, bind_dst} (var_env, ap_selections, var_heap, cs)
+		| isLowerCaseName ident.id_name
+			# (entry,cs_symbol_table) = readPtr ident.id_info cs.cs_symbol_table
+			# (rhs_var, var_heap) = allocate_free_var ident var_heap
+			  cs = checkPatternVariable def_level entry ident rhs_var.fv_info_ptr { cs & cs_symbol_table = cs_symbol_table }
+			= ([ident : var_env], [ { bind_src = rhs_var, bind_dst = bind_dst } : ap_selections], var_heap, cs)
+		// further with next alternative
+	check_rhs _ _ (var_env, ap_selections, var_heap, cs)
+		= (var_env, ap_selections, var_heap, 
+			{ cs & cs_error = checkError "" "variable expected on right hand side of array pattern" cs.cs_error })
+checkPattern expr opt_var p_input accus ps e_info cs
+	= abort "checkPattern: do not know how to handle pattern" ---> expr
+
+
+
+checkPatternConstructor :: !Index !Bool !SymbolTableEntry !Ident !(Optional (Bind Ident VarInfoPtr)) !*PatternState !*ExpressionInfo !*CheckState
+	-> (!AuxiliaryPattern, !*PatternState, !*ExpressionInfo, !*CheckState);
+checkPatternConstructor _ _ {ste_kind = STE_Empty} ident _  ps e_info cs=:{cs_error}
+	= (AP_Empty ident, ps, e_info, { cs & cs_error = checkError ident " not defined" cs_error })
+checkPatternConstructor mod_index is_expr_list {ste_kind = STE_FunctionOrMacro _,ste_index} ident opt_var  ps=:{ps_fun_defs} e_info cs=:{cs_error,cs_x}
+	# ({fun_symb,fun_arity,fun_kind,fun_priority},ps_fun_defs) = ps_fun_defs![ste_index]
+	  ps = { ps & ps_fun_defs = ps_fun_defs }
+	| case fun_kind of FK_DefMacro->True ; FK_ImpMacro->True; _ -> False
+		| is_expr_list
+			# macro_symbol = { glob_object = MakeDefinedSymbol fun_symb ste_index fun_arity, glob_module = cs_x.x_main_dcl_module_n }
+	 		= (AP_Constant APK_Macro macro_symbol fun_priority, ps, e_info, cs)
+		| fun_arity == 0
+			# (pattern, ps, ef_modules, ef_cons_defs, cs_error)
+					= unfoldPatternMacro mod_index ste_index [] opt_var ps e_info.ef_modules e_info.ef_cons_defs cs_error
+			= (pattern, ps, { e_info & ef_modules = ef_modules, ef_cons_defs = ef_cons_defs }, { cs & cs_error = cs_error })
+			= (AP_Empty ident, ps, e_info, { cs & cs_error = checkError ident " not defined" cs_error })
+		= (AP_Empty ident, ps, e_info, { cs & cs_error = checkError fun_symb " not allowed in a pattern" cs_error })
+checkPatternConstructor mod_index is_expr_list {ste_index, ste_kind} cons_symb opt_var ps
+		e_info=:{ef_cons_defs,ef_modules} cs=:{cs_error}
+	# (cons_index, cons_module, cons_arity, cons_priority, cons_type_index, ef_cons_defs, ef_modules, cs_error)
+			= determine_pattern_symbol mod_index ste_index ste_kind cons_symb.id_name ef_cons_defs ef_modules cs_error
+	  e_info = { e_info & ef_cons_defs = ef_cons_defs, ef_modules = ef_modules }
+	  cons_symbol = { glob_object = MakeDefinedSymbol cons_symb cons_index cons_arity, glob_module = cons_module }
+   	| is_expr_list
+		= (AP_Constant (APK_Constructor cons_type_index) cons_symbol cons_priority, ps, e_info, { cs & cs_error = cs_error })
+	| cons_arity == 0
+		= (AP_Algebraic cons_symbol cons_type_index [] opt_var, ps, e_info, { cs & cs_error = cs_error })
+		= (AP_Algebraic cons_symbol cons_type_index [] opt_var, ps, e_info, { cs & cs_error = checkError cons_symb " constructor arguments are missing" cs_error })
+where
+	determine_pattern_symbol mod_index id_index STE_Constructor id_name cons_defs modules error
+		# ({cons_type={st_arity},cons_priority, cons_type_index}, cons_defs) = cons_defs![id_index]
+		= (id_index, mod_index, st_arity, cons_priority, cons_type_index, cons_defs, modules, error)
+	determine_pattern_symbol mod_index id_index (STE_Imported STE_Constructor import_mod_index) id_name cons_defs modules error
+		# ({dcl_common,dcl_conversions},modules) = modules![import_mod_index]
+		  {cons_type={st_arity},cons_priority, cons_type_index} = dcl_common.com_cons_defs.[id_index]
+		  id_index = convertIndex id_index (toInt STE_Constructor) dcl_conversions
+		= (id_index, import_mod_index, st_arity, cons_priority, cons_type_index, cons_defs, modules, error)
+	determine_pattern_symbol mod_index id_index id_kind id_name cons_defs modules error
+		= (id_index, NoIndex, 0, NoPrio, NoIndex, cons_defs, modules, checkError id_name " constructor expected" error)
+
+
+
+checkBoundPattern {bind_src,bind_dst} opt_var p_input (var_env, array_patterns) ps e_info cs=:{cs_symbol_table}
+	| isLowerCaseName bind_dst.id_name
+		# (entry, cs_symbol_table) = readPtr bind_dst.id_info cs_symbol_table
+		# (new_info_ptr, ps_var_heap) = newPtr VI_Empty ps.ps_var_heap
+		  cs = checkPatternVariable p_input.pi_def_level entry bind_dst new_info_ptr { cs & cs_symbol_table = cs_symbol_table }
+		  ps = { ps & ps_var_heap = ps_var_heap }
+		  new_var_env = [ bind_dst : var_env ]
+		= case opt_var of
+			Yes bind
+				-> checkPattern bind_src (Yes { bind_src = bind_dst, bind_dst = new_info_ptr }) p_input (new_var_env, array_patterns) ps
+					 	e_info { cs & cs_error = checkError bind.bind_src "pattern may be bound once only" cs.cs_error }
+			No
+				-> checkPattern bind_src (Yes { bind_src = bind_dst, bind_dst = new_info_ptr }) p_input (new_var_env, array_patterns) ps e_info cs
+	= checkPattern bind_src opt_var p_input (var_env, array_patterns) ps e_info { cs & cs_error = checkError bind_dst "variable expected" cs.cs_error }
+
+
+
+
+checkPatternVariable :: !Level !SymbolTableEntry !Ident !VarInfoPtr !*CheckState -> !*CheckState
+checkPatternVariable def_level entry=:{ste_def_level,ste_kind} ident=:{id_info} var_info cs=:{cs_symbol_table,cs_error}
+	| ste_kind == STE_Empty || def_level > ste_def_level
+		# entry = {ste_kind = STE_Variable var_info, ste_index = NoIndex, ste_def_level = def_level, ste_previous = entry }
+		= { cs & cs_symbol_table = cs_symbol_table <:= (id_info,entry)}
+		= { cs & cs_error = checkError ident "(pattern variable) already defined" cs_error }
+
+
+
+checkIdentPattern :: !Bool !Ident !(Optional (Bind Ident VarInfoPtr)) !PatternInput !(![Ident], ![ArrayPattern]) !*PatternState !*ExpressionInfo !*CheckState
+	-> (!AuxiliaryPattern, !(![Ident], ![ArrayPattern]), !*PatternState, !*ExpressionInfo, !*CheckState)
+checkIdentPattern is_expr_list id=:{id_name,id_info} opt_var {pi_def_level, pi_mod_index} accus=:(var_env, array_patterns)
+					ps e_info cs=:{cs_symbol_table}
+	# (entry, cs_symbol_table) = readPtr id_info cs_symbol_table
+	| isLowerCaseName id_name
+		# (new_info_ptr, ps_var_heap) = newPtr VI_Empty ps.ps_var_heap
+		  cs = checkPatternVariable pi_def_level entry id new_info_ptr { cs & cs_symbol_table = cs_symbol_table }
+		= (AP_Variable id new_info_ptr opt_var, ([ id : var_env ], array_patterns), { ps & ps_var_heap = ps_var_heap}, e_info, cs)
+		# (pattern, ps, e_info, cs) = checkPatternConstructor pi_mod_index is_expr_list entry id opt_var ps e_info { cs & cs_symbol_table = cs_symbol_table }
+		= (pattern, accus, ps, e_info, cs)
+
+
+
+convertSubPatterns :: [AuxiliaryPattern] Expression Position *(Heap VarInfo) *(Heap ExprInfo) u:[Ptr ExprInfo] *CheckState -> *(!.[FreeVar],!Expression,!Position,!*Heap VarInfo,!*Heap ExprInfo,!u:[Ptr ExprInfo],!*CheckState);
+convertSubPatterns [] result_expr pattern_position var_store expr_heap opt_dynamics cs
+	= ([], result_expr, pattern_position, var_store, expr_heap, opt_dynamics, cs)
+convertSubPatterns [pattern : patterns] result_expr pattern_position var_store expr_heap opt_dynamics cs
+	# (var_args, result_expr, pattern_position, var_store, expr_heap, opt_dynamics, cs) 
+			= convertSubPatterns patterns result_expr pattern_position var_store expr_heap opt_dynamics cs
+	  (var_arg, result_expr, pattern_position, var_store, expr_heap, opt_dynamics, cs)
+	  		= convertSubPattern pattern result_expr pattern_position var_store expr_heap opt_dynamics cs
+	= ([var_arg : var_args], result_expr, pattern_position, var_store, expr_heap, opt_dynamics, cs)
+
+convertSubPattern :: AuxiliaryPattern Expression Position *(Heap VarInfo) *(Heap ExprInfo) u:[Ptr ExprInfo] *CheckState -> *(!FreeVar,!Expression,!Position,!*Heap VarInfo,!*Heap ExprInfo,!u:[Ptr ExprInfo],!*CheckState);
+convertSubPattern (AP_Variable name var_info (Yes {bind_src,bind_dst})) result_expr pattern_position var_store expr_heap opt_dynamics cs
+	# (var_expr_ptr, expr_heap) = newPtr EI_Empty expr_heap
+	  bound_var = { var_name = bind_src, var_info_ptr = bind_dst, var_expr_ptr = var_expr_ptr }
+	  free_var = { fv_name = bind_src, fv_info_ptr = bind_dst, fv_def_level = NotALevel, fv_count = 0 }
+	  (let_expr, expr_heap)	= buildLetExpression [] [{lb_src = Var bound_var,
+	  			lb_dst = { fv_name = name, fv_info_ptr = var_info, fv_def_level = NotALevel, fv_count = 0 },
+	  			lb_position = NoPos }] result_expr NoPos expr_heap
+	= (free_var, let_expr, pattern_position, var_store, expr_heap, opt_dynamics, cs)
+convertSubPattern (AP_Variable name var_info No) result_expr pattern_position var_store expr_heap opt_dynamics cs
+	= ({ fv_name = name, fv_info_ptr = var_info, fv_def_level = NotALevel, fv_count = 0 }, result_expr, pattern_position, 
+		var_store, expr_heap, opt_dynamics, cs)
+convertSubPattern (AP_Algebraic cons_symbol type_index args opt_var) result_expr pattern_position
+					var_store expr_heap opt_dynamics cs
+	# (var_args, result_expr, pattern_position, var_store, expr_heap, opt_dynamics, cs)
+			= convertSubPatterns args result_expr pattern_position var_store expr_heap opt_dynamics cs
+	  type_symbol = { glob_module = cons_symbol.glob_module, glob_object = type_index }
+	  alg_pattern = { ap_symbol = cons_symbol, ap_vars = var_args, ap_expr = result_expr, ap_position = pattern_position }
+	  case_guards = AlgebraicPatterns type_symbol [alg_pattern]
+	  ({bind_src,bind_dst}, var_store) = determinePatternVariable opt_var var_store
+	  (var_expr_ptr, expr_heap) = newPtr EI_Empty expr_heap
+	  (case_expr_ptr, expr_heap) = newPtr EI_Empty expr_heap
+	= ({ fv_name = bind_src, fv_info_ptr = bind_dst, fv_def_level = NotALevel, fv_count = 0 },
+		Case { case_expr = Var { var_name = bind_src, var_info_ptr = bind_dst, var_expr_ptr = var_expr_ptr },
+				case_guards = case_guards, case_default = No, case_ident = No, case_info_ptr = case_expr_ptr,
+				case_default_pos = NoPos },
+		NoPos, var_store, expr_heap, opt_dynamics, cs)
+convertSubPattern (AP_Basic basic_val opt_var) result_expr pattern_position var_store expr_heap opt_dynamics cs
+	# (basic_type, cs) = typeOfBasicValue basic_val cs
+	  case_guards = BasicPatterns basic_type [{ bp_value = basic_val, bp_expr = result_expr, bp_position = pattern_position }]
+  	  ({bind_src,bind_dst}, var_store) = determinePatternVariable opt_var var_store
+	  (var_expr_ptr, expr_heap) = newPtr EI_Empty expr_heap
+	  (case_expr_ptr, expr_heap) = newPtr EI_Empty expr_heap
+	= ({ fv_name = bind_src, fv_info_ptr = bind_dst, fv_def_level = NotALevel, fv_count = 0 },
+		Case { case_expr = Var { var_name = bind_src, var_info_ptr = bind_dst, var_expr_ptr = var_expr_ptr },
+			  case_guards = case_guards, case_default = No, case_ident = No, case_info_ptr = case_expr_ptr,
+			  case_default_pos = NoPos},
+		NoPos, var_store, expr_heap, opt_dynamics, cs)
+convertSubPattern (AP_Dynamic pattern type opt_var) result_expr pattern_position var_store expr_heap opt_dynamics cs
+	# (var_arg, result_expr, pattern_position, var_store, expr_heap, opt_dynamics, cs)
+			= convertSubPattern pattern result_expr pattern_position var_store expr_heap opt_dynamics cs
+ 	  ({bind_src,bind_dst}, var_store) = determinePatternVariable opt_var var_store
+	  (var_expr_ptr, expr_heap) = newPtr EI_Empty expr_heap
+	  (type_case_info_ptr, expr_heap) = newPtr EI_Empty expr_heap
+	  (dynamic_info_ptr, expr_heap) = newPtr (EI_DynamicType type opt_dynamics) expr_heap
+ 	  type_case_patterns = [{ dp_var = var_arg, dp_type = dynamic_info_ptr, dp_rhs = result_expr, dp_type_patterns_vars = [],
+ 	  						dp_type_code = TCE_Empty, dp_position = pattern_position }]
+	= ({ fv_name = bind_src, fv_info_ptr = bind_dst, fv_def_level = NotALevel, fv_count = 0 },
+		buildTypeCase (Var { var_name = bind_src, var_info_ptr = bind_dst, var_expr_ptr = var_expr_ptr }) 
+							type_case_patterns No type_case_info_ptr,
+		NoPos, var_store, expr_heap, [dynamic_info_ptr], cs)
+convertSubPattern (AP_WildCard opt_var) result_expr pattern_position var_store expr_heap opt_dynamics cs
+ 	# ({bind_src,bind_dst}, var_store) = determinePatternVariable opt_var var_store
+	= ({ fv_name = bind_src, fv_info_ptr = bind_dst, fv_def_level = NotALevel, fv_count = 0  }, result_expr, pattern_position,
+		var_store, expr_heap, opt_dynamics, cs)
+convertSubPattern (AP_Empty _) result_expr pattern_position var_store expr_heap opt_dynamics cs
+	= convertSubPattern (AP_WildCard No) EE pattern_position var_store expr_heap opt_dynamics cs
+
+
+checkAndTransformPatternIntoBind free_vars [{nd_dst,nd_alts,nd_locals,nd_position} : local_defs] e_input=:{ei_expr_level,ei_mod_index} e_state e_info cs
+	# cs = pushErrorAdmin (newPosition {id_name="node definition", id_info=nilPtr} nd_position) cs
+	# (bind_src, free_vars, e_state, e_info, cs) = checkRhs free_vars nd_alts nd_locals e_input e_state e_info cs	
+	  (binds_of_bind, es_var_heap, es_expr_heap, e_info, cs)
+			= transfromPatternIntoBind ei_mod_index ei_expr_level nd_dst bind_src nd_position
+				e_state.es_var_heap e_state.es_expr_heap e_info cs
+	  e_state = { e_state & es_var_heap = es_var_heap, es_expr_heap = es_expr_heap }
+	  (binds_of_local_defs, free_vars, e_state, e_info, cs) = checkAndTransformPatternIntoBind free_vars local_defs e_input e_state e_info cs
+	= (binds_of_bind ++ binds_of_local_defs, free_vars, e_state, e_info, popErrorAdmin cs)
+checkAndTransformPatternIntoBind free_vars [] e_input e_state e_info cs
+	= ([], free_vars, e_state, e_info, cs)
+
+
+
+transfromPatternIntoBind :: !Index !Level !AuxiliaryPattern !Expression !Position !*VarHeap !*ExpressionHeap !*ExpressionInfo !*CheckState
+	-> *(![LetBind], !*VarHeap, !*ExpressionHeap,  !*ExpressionInfo, !*CheckState)
+transfromPatternIntoBind mod_index def_level (AP_Variable name var_info _) src_expr position var_store expr_heap e_info cs
+	# bind = {lb_src = src_expr, lb_dst = { fv_name = name, fv_info_ptr = var_info, fv_def_level = def_level, fv_count = 0 }, lb_position = position }
+	= ([bind], var_store, expr_heap, e_info, cs)
+transfromPatternIntoBind mod_index def_level (AP_Algebraic cons_symbol=:{glob_module,glob_object=ds_cons=:{ds_arity, ds_index, ds_ident}} type_index args opt_var)
+		src_expr position var_store expr_heap e_info=:{ef_type_defs,ef_modules} cs
+	# (src_expr, opt_var_bind, var_store, expr_heap) = bind_opt_var opt_var src_expr position var_store expr_heap
+	| ds_arity == 0
+		= ([], var_store, expr_heap, e_info, { cs & cs_error = checkError ds_ident " constant not allowed in a node pattern" cs.cs_error})
+	# (is_tuple, cs) = is_tuple_symbol glob_module ds_index cs
+	| is_tuple
+		# (tuple_var, tuple_bind, var_store, expr_heap) = bind_match_expr src_expr opt_var_bind position var_store expr_heap
+		= transform_sub_patterns mod_index def_level args ds_cons 0 tuple_var tuple_bind position var_store expr_heap e_info cs
+		# ({td_rhs}, ef_type_defs, ef_modules) = get_type_def mod_index glob_module type_index ef_type_defs ef_modules
+		  e_info = { e_info & ef_type_defs = ef_type_defs, ef_modules = ef_modules }
+		= case td_rhs of
+			RecordType {rt_fields}
+				| size rt_fields == 1
+					-> transform_sub_patterns_of_record mod_index def_level args rt_fields glob_module 0
+							src_expr opt_var_bind position var_store expr_heap e_info cs
+					# (record_var, record_bind, var_store, expr_heap)
+						= bind_match_expr src_expr opt_var_bind position var_store expr_heap
+					-> transform_sub_patterns_of_record mod_index def_level args rt_fields glob_module 0
+							record_var record_bind position var_store expr_heap e_info cs
+			_
+				| ds_arity == 1
+		  			# (binds, var_store, expr_heap, e_info, cs)
+						= transfromPatternIntoBind mod_index def_level (hd args) (MatchExpr No cons_symbol src_expr)
+								position var_store expr_heap e_info cs
+					-> (opt_var_bind ++ binds, var_store, expr_heap, e_info, cs)
+					# (tuple_type, cs) = getPredefinedGlobalSymbol (GetTupleTypeIndex ds_arity) PD_PredefinedModule STE_Type ds_arity cs
+					  (tuple_cons, cs) = getPredefinedGlobalSymbol (GetTupleConsIndex ds_arity) PD_PredefinedModule STE_Constructor ds_arity cs
+					  (match_var, match_bind, var_store, expr_heap)
+						=  bind_match_expr (MatchExpr (Yes tuple_type) cons_symbol src_expr) opt_var_bind position var_store expr_heap
+					-> transform_sub_patterns mod_index def_level args tuple_cons.glob_object 0 match_var match_bind
+							position var_store expr_heap e_info cs
+where
+	get_type_def mod_index type_mod_index type_index ef_type_defs ef_modules
+		| mod_index == type_mod_index
+			# (type_def, ef_type_defs) = ef_type_defs![type_index]
+			= (type_def, ef_type_defs, ef_modules)
+			# ({dcl_common},  ef_modules) = ef_modules![type_mod_index]
+			= (dcl_common.com_type_defs.[type_index], ef_type_defs, ef_modules)
+		
+	is_tuple_symbol cons_module cons_index cs
+		# (tuple_2_symbol, cs) = getPredefinedGlobalSymbol (GetTupleConsIndex 2) PD_PredefinedModule STE_Constructor 2 cs
+		= (tuple_2_symbol.glob_module == cons_module &&
+		   tuple_2_symbol.glob_object.ds_index <= cons_index && cons_index <= tuple_2_symbol.glob_object.ds_index + 30, cs)
+
+	transform_sub_patterns mod_index def_level [pattern : patterns] tup_id tup_index arg_var all_binds position var_store expr_heap e_info cs
+		# (this_arg_var, expr_heap)
+				= adjust_match_expression arg_var expr_heap
+		  match_expr
+		  		= TupleSelect tup_id tup_index this_arg_var
+		  (binds, var_store, expr_heap, e_info, cs)
+		  		= transfromPatternIntoBind mod_index def_level pattern match_expr position var_store expr_heap e_info cs
+		= transform_sub_patterns mod_index def_level patterns tup_id (inc tup_index) arg_var (binds ++ all_binds)
+				position var_store expr_heap e_info cs
+	transform_sub_patterns mod_index _ [] _ _ _ binds _ var_store expr_heap e_info cs
+		= (binds, var_store, expr_heap, e_info, cs)
+
+	transform_sub_patterns_of_record mod_index def_level [pattern : patterns] fields field_module field_index record_expr
+			all_binds position var_store expr_heap e_info cs
+		# {fs_name, fs_index} = fields.[field_index]
+		  selector = { glob_module = field_module, glob_object = MakeDefinedSymbol fs_name fs_index 1}
+		  (this_record_expr, expr_heap) = adjust_match_expression record_expr expr_heap
+		  (binds, var_store, expr_heap, e_info, cs)
+				= transfromPatternIntoBind mod_index def_level pattern (Selection No this_record_expr [ RecordSelection selector field_index ])
+						position var_store expr_heap e_info cs
+		= transform_sub_patterns_of_record mod_index def_level patterns fields field_module (inc field_index) record_expr
+				(binds ++ all_binds) position var_store expr_heap e_info cs
+	transform_sub_patterns_of_record mod_index _ [] _ _ _ _ binds _ var_store expr_heap e_info cs
+		= (binds, var_store, expr_heap, e_info, cs)
+
+	bind_opt_var (Yes {bind_src,bind_dst}) src_expr position var_heap expr_heap
+		# free_var = { fv_name = bind_src, fv_info_ptr = bind_dst, fv_def_level = NotALevel, fv_count = 0 }
+		  (var_expr_ptr, expr_heap) = newPtr EI_Empty expr_heap
+		  bound_var = { var_name = bind_src, var_info_ptr = bind_dst, var_expr_ptr = var_expr_ptr }
+		= (Var bound_var, [{lb_src = src_expr, lb_dst = free_var, lb_position = position}], var_heap <:= (bind_dst, VI_Empty), expr_heap)
+	bind_opt_var No src_expr _ var_heap expr_heap
+		= (src_expr, [], var_heap, expr_heap)
+		
+	bind_match_expr var_expr=:(Var var) opt_var_bind _ var_heap expr_heap
+		= (var_expr, opt_var_bind, var_heap, expr_heap)
+	bind_match_expr match_expr opt_var_bind position var_heap expr_heap
+		# new_name = newVarId "_x"
+		  (var_info_ptr, var_heap) = newPtr VI_Empty var_heap
+//		  (var_expr_ptr, expr_heap) = newPtr EI_Empty expr_heap
+		  bound_var = { var_name = new_name, var_info_ptr = var_info_ptr, var_expr_ptr = nilPtr }
+		  free_var = { fv_name = new_name, fv_info_ptr = var_info_ptr, fv_def_level = def_level, fv_count = 0 }
+		= (Var bound_var, [{lb_src = match_expr, lb_dst = free_var, lb_position = position } : opt_var_bind], var_heap, expr_heap)
+
+	adjust_match_expression (Var var) expr_heap
+		# (var_expr_ptr, expr_heap) = newPtr EI_Empty expr_heap
+		= (Var { var & var_expr_ptr = var_expr_ptr }, expr_heap)
+	adjust_match_expression match_expr expr_heap
+		= (match_expr, expr_heap)
+transfromPatternIntoBind mod_index def_level (AP_WildCard _) src_expr _ var_store expr_heap e_info cs
+	= ([], var_store, expr_heap, e_info, cs)
+transfromPatternIntoBind _ _ pattern src_expr _ var_store expr_heap e_info cs
+	= ([], var_store, expr_heap, e_info, { cs & cs_error = checkError "<pattern>" " illegal node pattern" cs.cs_error})
+
+
+
+unfoldPatternMacro mod_index macro_index macro_args opt_var ps=:{ps_var_heap, ps_fun_defs} modules cons_defs error
+	# (macro, ps_fun_defs) = ps_fun_defs![macro_index]
+	= case macro.fun_body of
+		TransformedBody {tb_args,tb_rhs}
+			| no_sharing tb_args
+				# ums = { ums_var_heap = fold2St bind_var tb_args macro_args ps_var_heap, ums_modules = modules, ums_cons_defs = cons_defs, ums_error = error }
+				  (pattern, {ums_var_heap,ums_modules,ums_cons_defs,ums_error}) = unfold_pattern_macro mod_index macro.fun_symb opt_var tb_rhs ums
+				-> (pattern, { ps_fun_defs = ps_fun_defs, ps_var_heap = ums_var_heap}, ums_modules, ums_cons_defs, ums_error)
+				-> (AP_Empty macro.fun_symb, { ps_fun_defs = ps_fun_defs, ps_var_heap = ps_var_heap},
+						modules, cons_defs, checkError macro.fun_symb " sharing not allowed" error)
+		_
+			-> (AP_Empty macro.fun_symb, { ps_fun_defs = ps_fun_defs, ps_var_heap = ps_var_heap},
+					modules, cons_defs, checkError macro.fun_symb " illegal macro in pattern" error)
+	
+where
+	no_sharing [{fv_count} : args]
+		= fv_count <= 1 && no_sharing args
+	no_sharing []
+		= True
+	
+	bind_var {fv_info_ptr} pattern ps_var_heap
+		= ps_var_heap <:= (fv_info_ptr, VI_Pattern pattern)
+
+	unfold_pattern_macro mod_index macro_ident _ (Var {var_name,var_info_ptr}) ums=:{ums_var_heap}
+		# (VI_Pattern pattern, ums_var_heap) = readPtr var_info_ptr ums_var_heap
+		= (pattern, { ums & ums_var_heap = ums_var_heap})
+	unfold_pattern_macro mod_index macro_ident opt_var (App {app_symb,app_args}) ums
+		= unfold_application  mod_index macro_ident opt_var app_symb app_args ums
+	where
+		unfold_application  mod_index macro_ident opt_var {symb_kind=SK_Constructor {glob_module,glob_object},symb_name,symb_arity} args 
+										ums=:{ums_cons_defs, ums_modules,ums_error}
+				# (cons_def, cons_index, ums_cons_defs, ums_modules) = get_cons_def mod_index glob_module glob_object ums_cons_defs ums_modules
+				| cons_def.cons_type.st_arity == symb_arity
+					# (patterns, ums) = mapSt (unfold_pattern_macro mod_index macro_ident No) app_args { ums & ums_cons_defs = ums_cons_defs, ums_modules = ums_modules }
+					  cons_symbol = { glob_object = MakeDefinedSymbol symb_name cons_index symb_arity, glob_module = glob_module }	
+					= (AP_Algebraic cons_symbol cons_def.cons_type_index patterns opt_var, ums)	
+					= (AP_Empty cons_def.cons_symb, { ums & ums_cons_defs = ums_cons_defs, ums_modules = ums_modules,
+							ums_error = checkError cons_def.cons_symb " missing argument(s)" ums_error })
+
+		get_cons_def mod_index cons_mod cons_index cons_defs modules
+			| mod_index == cons_mod
+				# (cons_def, cons_defs) = cons_defs![cons_index]
+				= (cons_def, cons_index, cons_defs, modules)
+				# ({dcl_common,dcl_conversions}, modules) = modules![cons_mod]
+				  cons_def = dcl_common.com_cons_defs.[cons_index]
+				= (cons_def, convertIndex cons_index (toInt STE_Constructor) dcl_conversions, cons_defs, modules)
+
+	unfold_pattern_macro mod_index macro_ident opt_var (BasicExpr bv bt) ums
+		= (AP_Basic bv opt_var, ums)
+	unfold_pattern_macro mod_index macro_ident opt_var expr ums=:{ums_error}
+		= (AP_Empty macro_ident, { ums & ums_error = checkError macro_ident " illegal rhs for a pattern macro" ums_error })
+	
+	
+			
+checkSelectors end_with_update free_vars [ selector : selectors ] e_input e_state e_info cs
+	| isEmpty selectors
+		# (selector, free_vars, e_state, e_info, cs) = check_selector end_with_update free_vars selector e_input e_state e_info cs
+		= ([ selector ], free_vars, e_state, e_info, cs)
+		# (selector, free_vars, e_state, e_info, cs) = check_selector cEndWithSelection free_vars selector e_input e_state e_info cs
+		  (selectors, free_vars, e_state, e_info, cs) = checkSelectors end_with_update free_vars selectors e_input e_state e_info cs
+		= ([ selector : selectors ], free_vars, e_state, e_info, cs)
+where		
+	check_selector _ free_vars (PS_Record selector=:{id_info,id_name} opt_type) e_input=:{ei_mod_index} e_state
+			e_info=:{ef_selector_defs, ef_modules} cs=:{cs_symbol_table}
+		# (entry, cs_symbol_table) = readPtr id_info cs_symbol_table
+		# selectors = retrieveSelectorIndexes ei_mod_index entry 
+		  (field_module, field_index, field_nr, ef_selector_defs, ef_modules, cs)
+		  		= get_field_nr ei_mod_index selector opt_type selectors ef_selector_defs ef_modules { cs & cs_symbol_table = cs_symbol_table }
+		= (RecordSelection { glob_object = MakeDefinedSymbol selector field_index 1, glob_module = field_module } field_nr, free_vars, e_state,
+								{e_info & ef_selector_defs = ef_selector_defs, ef_modules = ef_modules }, cs)
+	where					
+		get_field_nr :: !Index !Ident !(Optional Ident) ![Global Index] !u:{#SelectorDef} !v:{# DclModule} !*CheckState
+				-> (!Index, !Index, !Index, u:{#SelectorDef}, v:{#DclModule}, !*CheckState)
+		get_field_nr mod_index sel_id _ [] selector_defs modules cs=:{cs_error}
+			= (NoIndex, NoIndex, NoIndex, selector_defs, modules, { cs & cs_error = checkError id_name " selector not defined" cs_error })
+		get_field_nr mod_index sel_id (Yes type_id=:{id_info}) selectors selector_defs modules cs=:{cs_symbol_table,cs_error}
+			# (entry, cs_symbol_table) = readPtr id_info cs_symbol_table
+			# (type_index, type_module) = retrieveGlobalDefinition entry STE_Type mod_index
+			| type_index <> NotFound
+				# (selector_index, selector_offset, selector_defs, modules)
+						= determine_selector mod_index type_module type_index selectors selector_defs modules
+				| selector_offset <> NoIndex
+					= (type_module, selector_index, selector_offset, selector_defs, modules, { cs & cs_symbol_table = cs_symbol_table })
+					= (NoIndex, NoIndex, NoIndex, selector_defs, modules, { cs & cs_symbol_table = cs_symbol_table,
+								cs_error = checkError id_name " selector not defined" cs_error })
+				= (NoIndex, NoIndex, NoIndex, selector_defs, modules, { cs & cs_symbol_table = cs_symbol_table,
+						cs_error = checkError type_id " type not defined" cs_error })
+		get_field_nr mod_index sel_id No [{glob_object,glob_module}] selector_defs modules cs
+			| mod_index == glob_module
+				# (selector_offset,selector_defs) = selector_defs![glob_object].sd_field_nr
+				= (glob_module, glob_object, selector_offset, selector_defs, modules, cs)
+				# (selector_offset,modules) = modules![glob_module].dcl_common.com_selector_defs.[glob_object].sd_field_nr
+				= (glob_module, glob_object, selector_offset, selector_defs, modules, cs)
+		get_field_nr mod_index sel_id No _  selector_defs modules cs=:{cs_error}
+			= (NoIndex, NoIndex, NoIndex, selector_defs, modules, { cs & cs_error = checkError sel_id " ambiguous selector specified" cs_error })
+
+		determine_selector :: !Index !Index !Index ![Global Index] !u:{# SelectorDef} !v:{# DclModule} -> (!Int, !Int, !u:{# SelectorDef}, !v:{# DclModule})
+		determine_selector mod_index type_mod_index type_index [] selector_defs modules
+			= (NoIndex, NoIndex, selector_defs, modules)
+		determine_selector mod_index type_mod_index type_index [{glob_module, glob_object} : selectors] selector_defs modules
+			| type_mod_index == glob_module
+				| type_mod_index == mod_index
+					#! selector_def = selector_defs.[glob_object]
+					| selector_def.sd_type_index == type_index
+						= (glob_object, selector_def.sd_field_nr, selector_defs, modules)
+						= determine_selector mod_index type_mod_index type_index selectors selector_defs modules
+					#! {dcl_common={com_selector_defs}} = modules.[glob_module]
+					#! selector_def = com_selector_defs.[glob_object]
+					| selector_def.sd_type_index == type_index
+						= (glob_object, selector_def.sd_field_nr, selector_defs, modules)
+						= determine_selector mod_index type_mod_index type_index selectors selector_defs modules
+				= determine_selector mod_index type_mod_index type_index selectors selector_defs modules
+
+	check_selector end_with_update free_vars (PS_Array index_expr) e_input e_state e_info cs
+		| end_with_update
+			# (glob_select_symb, cs) = getPredefinedGlobalSymbol PD_ArrayUpdateFun PD_StdArray STE_Member 3 cs
+			= checkArraySelection glob_select_symb free_vars index_expr e_input e_state e_info cs
+			# (glob_select_symb, cs) = getPredefinedGlobalSymbol PD_ArraySelectFun PD_StdArray STE_Member 2 cs
+			= checkArraySelection glob_select_symb free_vars index_expr e_input e_state e_info cs
+
+
+
+checkArraySelection glob_select_symb free_vars index_expr e_input e_state e_info cs
+	# (index_expr, free_vars, e_state, e_info, cs) = checkExpression free_vars index_expr e_input e_state e_info cs
+	  (new_info_ptr, es_expr_heap) = newPtr EI_Empty e_state.es_expr_heap
+	= (ArraySelection glob_select_symb new_info_ptr index_expr, free_vars, { e_state & es_expr_heap = es_expr_heap }, e_info, cs)
+
+
+
+checkFields :: !Index ![FieldAssignment] !(Optional Ident) !u:ExpressionInfo !*CheckState
+	-> (!Optional ((Global DefinedSymbol), Index, [Bind ParsedExpr (Global FieldSymbol)]), !u:ExpressionInfo, !*CheckState)
+checkFields mod_index field_ass opt_type e_info=:{ef_selector_defs,ef_type_defs,ef_modules} cs
+	# (ok, field_ass, cs) = check_fields field_ass cs
+	| ok
+		# (opt_type_def, ef_selector_defs, ef_type_defs, ef_modules, cs)
+				= determine_record_type mod_index opt_type field_ass ef_selector_defs ef_type_defs ef_modules cs
+		  e_info = { e_info & ef_selector_defs = ef_selector_defs, ef_type_defs = ef_type_defs, ef_modules = ef_modules}
+		= case opt_type_def of
+			Yes ({td_index,td_rhs = RecordType {rt_constructor,rt_fields}}, type_mod_index)
+				# (field_exprs, cs_error) = check_and_rearrange_fields type_mod_index 0 rt_fields field_ass cs.cs_error
+				-> (Yes ({ glob_object = rt_constructor, glob_module = type_mod_index }, td_index, field_exprs), e_info, { cs & cs_error = cs_error })
+			Yes _
+				# (Yes type_ident) = opt_type
+				-> (No, e_info, { cs & cs_error = checkError type_ident "not a record constructor" cs.cs_error })
+			No
+				-> (No, e_info, cs)
+		= (No, e_info, cs)
+where
+
+	check_fields [ bind=:{bind_dst} : field_ass ] cs=:{cs_symbol_table,cs_error}
+		# (entry, cs_symbol_table) = readPtr bind_dst.id_info cs_symbol_table
+		# fields = retrieveSelectorIndexes mod_index entry 
+		| isEmpty fields
+			= (False, [], { cs & cs_symbol_table = cs_symbol_table, cs_error = checkError bind_dst "not defined as a record field" cs_error })
+			# (ok, field_ass, cs) = check_fields field_ass { cs & cs_symbol_table = cs_symbol_table }
+			= (ok, [{bind & bind_dst = (bind_dst, fields)} : field_ass], cs)
+	check_fields [] cs
+		= (True, [], cs)
+
+	try_to_get_unique_field []
+		= No
+	try_to_get_unique_field [ {bind_dst = (field_id, [field])} : fields ]
+		= Yes field
+	try_to_get_unique_field [ _ : fields ]
+		= try_to_get_unique_field fields
+	
+	determine_record_type mod_index (Yes type_id=:{id_info}) _ selector_defs type_defs modules cs=:{cs_symbol_table, cs_error}
+		# (entry, cs_symbol_table) = readPtr id_info cs_symbol_table
+		# (type_index, type_mod_index) = retrieveGlobalDefinition entry STE_Type mod_index
+		| type_index <> NotFound
+			| mod_index == type_mod_index
+			 	# (type_def, type_defs) = type_defs![type_index]
+			 	= (Yes (type_def, type_mod_index), selector_defs, type_defs, modules, { cs & cs_symbol_table = cs_symbol_table })
+				# (type_def, modules) = modules![type_mod_index].dcl_common.com_type_defs.[type_index]
+				= (Yes (type_def, type_mod_index), selector_defs, type_defs, modules, { cs & cs_symbol_table = cs_symbol_table })
+			= (No, selector_defs, type_defs, modules, { cs & cs_error = checkError type_id " not defined" cs_error, cs_symbol_table = cs_symbol_table})
+	determine_record_type mod_index No fields selector_defs type_defs modules cs=:{cs_error}
+		# succ = try_to_get_unique_field fields
+		= case succ of
+			Yes {glob_module, glob_object}
+				| glob_module == mod_index
+					# (selector_def, selector_defs) = selector_defs![glob_object]
+					  (type_def, type_defs) = type_defs![selector_def.sd_type_index]
+					-> (Yes (type_def, glob_module), selector_defs, type_defs, modules, cs)
+					# ({dcl_common={com_selector_defs,com_type_defs}}, modules) = modules![glob_module]
+					# selector_def = com_selector_defs.[glob_object]
+					  type_def = com_type_defs.[selector_def.sd_type_index]
+					-> (Yes (type_def,glob_module), selector_defs, type_defs, modules, cs)
+			No
+				-> (No, selector_defs, type_defs, modules, { cs & cs_error = checkError "" " could not determine the type of this record" cs.cs_error })
+
+	check_and_rearrange_fields :: Int Int {#FieldSymbol} ![Bind ParsedExpr (Ident,[Global .Int])] *ErrorAdmin -> ([Bind ParsedExpr .(Global FieldSymbol)],!.ErrorAdmin);
+	check_and_rearrange_fields mod_index field_index fields field_ass cs_error
+		| field_index < size fields
+			# (field_expr, field_ass) = look_up_field mod_index fields.[field_index] field_ass
+		 	  (field_exprs, cs_error) = check_and_rearrange_fields mod_index (inc field_index) fields field_ass cs_error
+			= ([field_expr : field_exprs], cs_error)
+		| isEmpty field_ass
+			= ([], cs_error)
+			= ([], foldSt field_error field_ass cs_error)
+
+	where			
+		look_up_field mod_index field []
+			= ({bind_src = PE_WildCard,  bind_dst = { glob_object = field, glob_module = mod_index }}, [])
+		look_up_field mod_index field=:{fs_index} [ass=:{bind_src, bind_dst = (_, fields)} : field_ass]
+			| field_list_contains_field mod_index fs_index fields
+				= ({bind_src = bind_src, bind_dst = { glob_module = mod_index, glob_object = field}}, field_ass)
+				# (field_expr, field_ass) = look_up_field mod_index field field_ass
+				= (field_expr, [ass : field_ass])
+
+		field_list_contains_field mod_index fs_index []
+			= False
+		field_list_contains_field mod_index fs_index [{glob_object,glob_module} : fields]
+			= mod_index == glob_module && fs_index == glob_object || field_list_contains_field mod_index fs_index fields
+
+		field_error {bind_dst=(field_id,_)} error
+			= checkError field_id " field is either multiply used or not a part of this record" error
+
+
+
+checkRhssAndTransformLocalDefs free_vars [] rhs_expr e_input e_state e_info cs
+	= (rhs_expr, free_vars, e_state, e_info, cs)
+checkRhssAndTransformLocalDefs free_vars loc_defs rhs_expr e_input e_state e_info cs
+	# (binds, free_vars, e_state, e_info, cs) = checkAndTransformPatternIntoBind free_vars loc_defs e_input e_state e_info cs
+	  (rhs_expr, es_expr_heap) = buildLetExpression [] binds rhs_expr NoPos e_state.es_expr_heap
+	= (rhs_expr, free_vars, { e_state & es_expr_heap = es_expr_heap }, e_info, cs)
+
+checkLhssOfLocalDefs :: .Int .Int LocalDefs *ExpressionState *ExpressionInfo *CheckState -> (!.[NodeDef AuxiliaryPattern],!(![Ident],![ArrayPattern]),!.ExpressionState,!.ExpressionInfo,!.CheckState);
+checkLhssOfLocalDefs def_level mod_index (CollectedLocalDefs {loc_functions={ir_from,ir_to},loc_nodes}) e_state=:{es_var_heap,es_fun_defs} e_info cs
+	# (loc_defs, accus, {ps_fun_defs,ps_var_heap}, e_info, cs)
+			= check_patterns loc_nodes {pi_def_level = def_level, pi_mod_index = mod_index, pi_is_node_pattern = True } ([], [])
+					{ps_fun_defs = es_fun_defs, ps_var_heap = es_var_heap} e_info cs
+	  (es_fun_defs, cs_symbol_table, cs_error) = addLocalFunctionDefsToSymbolTable def_level ir_from ir_to ps_fun_defs cs.cs_symbol_table cs.cs_error
+	= (loc_defs, accus, { e_state & es_fun_defs = es_fun_defs, es_var_heap = ps_var_heap }, e_info, { cs & cs_symbol_table = cs_symbol_table, cs_error = cs_error })
+where
+	check_patterns [ (_,node_def) : node_defs ] p_input accus var_store e_info cs
+		# (pattern, accus, var_store, e_info, cs) = checkPattern node_def.nd_dst No p_input accus var_store e_info cs
+		  (patterns, accus, var_store, e_info, cs) = check_patterns node_defs p_input accus var_store e_info cs
+		= ([{ node_def & nd_dst = pattern } : patterns], accus, var_store, e_info, cs)
+	check_patterns [] p_input accus var_store e_info cs
+		= ([], accus, var_store, e_info, cs)
+
+
+
+addArraySelections [] rhs_expr free_vars e_input e_state e_info cs
+	= (rhs_expr, free_vars, e_state, e_info, cs)
+addArraySelections array_patterns rhs_expr free_vars e_input e_state e_info cs
+	# (let_strict_binds, let_lazy_binds, free_vars, e_state, e_info, cs)
+			= foldSt (buildSelections e_input) array_patterns ([], [], free_vars, e_state, e_info, cs)
+	  (let_expr_ptr, es_expr_heap)
+	  		= newPtr EI_Empty e_state.es_expr_heap
+	= ( Let {let_strict_binds = let_strict_binds, let_lazy_binds = let_lazy_binds,
+				let_expr = rhs_expr, let_info_ptr = let_expr_ptr, let_expr_position = NoPos }
+	  , free_vars
+	  , { e_state & es_expr_heap = es_expr_heap}
+	  , e_info
+	  , cs
+	  )
+
+
+
+buildSelections e_input {ap_opt_var, ap_array_var, ap_selections}
+					(strict_binds, lazy_binds, free_vars, e_state, e_info, cs)
+	# (ap_array_var, [last_array_selection:lazy_binds], free_vars, e_state, e_info, cs)
+			= foldSt (build_sc e_input) (reverse ap_selections) // reverse to make cycle-in-spine behaviour compatible to Clean 1.3
+						(ap_array_var, lazy_binds, free_vars, e_state, e_info, cs)
+	  (lazy_binds, e_state)
+	  		= case ap_opt_var of
+	  			Yes { bind_src = opt_var_ident, bind_dst = opt_var_var_info_ptr }
+					# (bound_array_var, es_expr_heap) = allocate_bound_var ap_array_var e_state.es_expr_heap
+					  free_var = { fv_name = opt_var_ident, fv_info_ptr = opt_var_var_info_ptr, fv_def_level = NotALevel,
+					  				fv_count = 0 }
+	  				-> ([{ lb_dst = free_var, lb_src = Var bound_array_var, lb_position = NoPos }: lazy_binds],
+	  					{ e_state & es_expr_heap = es_expr_heap })
+	  			no	-> (lazy_binds, e_state)
+	= ([last_array_selection:strict_binds], lazy_binds, free_vars, e_state, e_info, cs)
+  where
+	build_sc e_input {bind_dst=parsed_index_exprs, bind_src=array_element_var} (ap_array_var, binds, free_vars, e_state, e_info, cs)
+		# (var_for_uselect_result, es_var_heap)
+				= allocate_free_var { id_name = "_x", id_info = nilPtr } e_state.es_var_heap
+		  (new_array_var, es_var_heap)
+		  		= allocate_free_var ap_array_var.fv_name es_var_heap
+		  (bound_array_var, es_expr_heap)
+		  		= allocate_bound_var ap_array_var e_state.es_expr_heap
+		  (bound_var_for_uselect_result, es_expr_heap)
+		  		= allocate_bound_var var_for_uselect_result es_expr_heap
+		  dimension
+		  		= length parsed_index_exprs
+		  (new_expr_ptrs, es_expr_heap)
+		  		= mapSt newPtr (repeatn dimension EI_Empty) es_expr_heap
+		  (tuple_cons, cs)
+		  		= getPredefinedGlobalSymbol (GetTupleConsIndex 2) PD_PredefinedModule STE_Constructor 2 cs
+		  (glob_select_symb, opt_tuple_type, cs)
+		  		= case dimension of
+		  			1	# (unq_select_symb, cs) = getPredefinedGlobalSymbol PD_UnqArraySelectFun PD_StdArray STE_Member 2 cs
+		  				-> (unq_select_symb, No, cs)
+		  			_	# (select_symb, cs) = getPredefinedGlobalSymbol PD_ArraySelectFun PD_StdArray STE_Member 2 cs
+						  (tuple_type, cs) = getPredefinedGlobalSymbol (GetTupleTypeIndex 2) PD_PredefinedModule STE_Type 2 cs
+		  				-> (select_symb, Yes tuple_type, cs)
+		  e_state
+		  		= { e_state & es_var_heap = es_var_heap, es_expr_heap = es_expr_heap }
+		  (index_exprs, (free_vars, e_state, e_info, cs))
+		  		= mapSt (check_index_expr e_input) parsed_index_exprs (free_vars, e_state, e_info, cs)
+		  selections
+		  		= [ ArraySelection glob_select_symb new_expr_ptr index_expr \\ new_expr_ptr<-new_expr_ptrs & index_expr<-index_exprs ]
+		= (	new_array_var
+		  ,	[ {lb_dst = var_for_uselect_result, lb_src = Selection opt_tuple_type (Var bound_array_var) selections, lb_position = NoPos }
+		    , {lb_dst = new_array_var, lb_src = TupleSelect tuple_cons.glob_object 1 (Var bound_var_for_uselect_result), lb_position = NoPos }
+		    , {lb_dst = array_element_var, lb_src = TupleSelect tuple_cons.glob_object 0 (Var bound_var_for_uselect_result), lb_position = NoPos }
+		  	: binds
+			]
+		  , free_vars
+		  , e_state
+		  , e_info 
+		  , cs
+		  )
+
+	check_index_expr e_input parsed_index_expr (free_vars, e_state, e_info, cs)
+		# (index_expr, free_vars, e_state, e_info, cs) = checkExpression free_vars parsed_index_expr e_input e_state e_info cs
+		= (index_expr, (free_vars, e_state, e_info, cs))
+		
+
+
+buildLetExpression :: ![LetBind] ![LetBind] !Expression !Position !*ExpressionHeap  -> (!Expression, !*ExpressionHeap)
+buildLetExpression [] [] expr _ expr_heap
+	= (expr, expr_heap)
+buildLetExpression let_strict_binds let_lazy_binds expr let_expr_position expr_heap
+	# (let_expr_ptr, expr_heap) = newPtr EI_Empty expr_heap
+	= (Let {let_strict_binds = let_strict_binds, let_lazy_binds = let_lazy_binds, let_expr = expr,
+			let_info_ptr = let_expr_ptr, let_expr_position = let_expr_position }, expr_heap)
+
+
+
+buildApplication :: !SymbIdent !Int !Int !Bool ![Expression] !*ExpressionState !*ErrorAdmin -> (!Expression,!*ExpressionState,!*ErrorAdmin)
+buildApplication symbol form_arity act_arity is_fun args e_state=:{es_expr_heap} error
+	| is_fun
+		# (new_info_ptr, es_expr_heap) = newPtr EI_Empty es_expr_heap
+		| form_arity < act_arity
+			# app = { app_symb = { symbol & symb_arity = form_arity }, app_args = take form_arity args, app_info_ptr = new_info_ptr }
+			= (App app @ drop form_arity args, { e_state & es_expr_heap = es_expr_heap }, error)
+			# app = { app_symb = { symbol & symb_arity = act_arity }, app_args = take form_arity args, app_info_ptr = new_info_ptr }
+			= (App app, { e_state & es_expr_heap = es_expr_heap }, error)
+		# app = App { app_symb = { symbol & symb_arity = act_arity }, app_args = args, app_info_ptr = nilPtr }
+		| form_arity < act_arity
+			= (app, e_state, checkError symbol.symb_name " used with too many arguments" error)
+			= (app, e_state, error)
+
+
+
+buildPattern mod_index (APK_Constructor type_index) cons_symb args opt_var ps e_info cs
+	= (AP_Algebraic cons_symb type_index args opt_var, ps, e_info, cs)
+buildPattern mod_index APK_Macro {glob_object} args opt_var ps e_info=:{ef_modules,ef_cons_defs} cs=:{cs_error}
+	# (pattern, ps, ef_modules, ef_cons_defs, cs_error)
+			= unfoldPatternMacro mod_index glob_object.ds_index args opt_var ps ef_modules ef_cons_defs cs_error
+	= (pattern, ps, { e_info & ef_modules = ef_modules, ef_cons_defs = ef_cons_defs }, { cs & cs_error = cs_error })
+
+
+
+//////////////////////////////////////////////////////////////////////////////////
+//////////////////////////////////////////////////////////////////////////////////
+//////////////////////////////////////////////////////////////////////////////////
+//////////////////////////////////////////////////////////////////////////////////
+//////////////////////////////////////////////////////////////////////////////////
+//////////////////////////////////////////////////////////////////////////////////
+//////////////////////////////////////////////////////////////////////////////////
+//////////////////////////////////////////////////////////////////////////////////
+//////////////////////////////////////////////////////////////////////////////////
+//////////////////////////////////////////////////////////////////////////////////
+//////////////////////////////////////////////////////////////////////////////////
+//////////////////////////////////////////////////////////////////////////////////
+//////////////////////////////////////////////////////////////////////////////////
+//////////////////////////////////////////////////////////////////////////////////
+//////////////////////////////////////////////////////////////////////////////////
+
+getPredefinedGlobalSymbol :: !Index !Index !STE_Kind !Int !*CheckState -> (!Global DefinedSymbol, !*CheckState)
+getPredefinedGlobalSymbol symb_index module_index req_ste_kind arity cs=:{cs_predef_symbols,cs_symbol_table}
+	# (pre_def_mod, cs_predef_symbols)	= cs_predef_symbols![module_index]
+	# mod_id							= pre_def_mod.pds_ident
+	# (mod_entry, cs_symbol_table)		= readPtr mod_id.id_info cs_symbol_table
+	| mod_entry.ste_kind == STE_ClosedModule
+		# (glob_object, cs) = get_predefined_symbol symb_index req_ste_kind arity mod_entry.ste_index
+										{ cs & cs_predef_symbols = cs_predef_symbols, cs_symbol_table = cs_symbol_table}
+		= ({ glob_object = glob_object, glob_module = mod_entry.ste_index }, cs)
+		= ({ glob_object = { ds_ident = { id_name = "** ERRONEOUS **", id_info = nilPtr }, ds_index = NoIndex, ds_arity = arity }, glob_module = NoIndex},
+				  		{ cs & cs_error = checkError mod_id "not imported" cs.cs_error, cs_predef_symbols = cs_predef_symbols, cs_symbol_table = cs_symbol_table })
+where
+	get_predefined_symbol :: !Index !STE_Kind !Int !Index !*CheckState -> (!DefinedSymbol,!*CheckState)
+	get_predefined_symbol symb_index req_ste_kind arity mod_index cs=:{cs_predef_symbols,cs_symbol_table,cs_error}
+		# (pre_def_symb, cs_predef_symbols)	= cs_predef_symbols![symb_index]
+		  symb_id							= pre_def_symb.pds_ident
+		  (symb_entry, cs_symbol_table) 	= readPtr symb_id.id_info cs_symbol_table
+		  cs = { cs & cs_predef_symbols = cs_predef_symbols, cs_symbol_table = cs_symbol_table }
+		| symb_entry.ste_kind == req_ste_kind
+			= ({ ds_ident = symb_id, ds_index = symb_entry.ste_index, ds_arity = arity }, cs)
+			= case symb_entry.ste_kind of
+				STE_Imported kind module_index
+					| mod_index == module_index && kind == req_ste_kind
+						-> ({ ds_ident = symb_id, ds_index = symb_entry.ste_index, ds_arity = arity }, cs)
+				_
+					-> ({ ds_ident = symb_id, ds_index = NoIndex, ds_arity = arity }, { cs & cs_error = checkError symb_id "undefined" cs.cs_error })
+		
+
+
+typeOfBasicValue :: !BasicValue !*CheckState -> (!BasicType, !*CheckState)
+typeOfBasicValue (BVI _) cs = (BT_Int, cs)
+typeOfBasicValue (BVC _) cs = (BT_Char, cs)
+typeOfBasicValue (BVB _) cs = (BT_Bool, cs)
+typeOfBasicValue (BVR _) cs = (BT_Real, cs)
+typeOfBasicValue (BVS _) cs
+	# ({glob_module,glob_object={ds_ident,ds_index,ds_arity}}, cs) = getPredefinedGlobalSymbol PD_StringType PD_PredefinedModule STE_Type 0 cs
+	= (BT_String (TA (MakeTypeSymbIdent { glob_object = ds_index, glob_module = glob_module } ds_ident ds_arity) []), cs)
+
+
+
+buildTypeCase type_case_dynamic type_case_patterns type_case_default type_case_info_ptr :==
+	Case {	case_expr = type_case_dynamic, case_guards = DynamicPatterns type_case_patterns, case_default = type_case_default, 
+			case_info_ptr = type_case_info_ptr, case_ident = No, case_default_pos = NoPos }
+
+
+
+determinePatternVariable (Yes bind) var_heap
+	= (bind, var_heap)
+determinePatternVariable No var_heap
+	# (new_info_ptr, var_heap) = newPtr VI_Empty var_heap
+	= ({ bind_src = newVarId "_x", bind_dst = new_info_ptr }, var_heap)
+
+
+
+pushErrorAdmin2 _ NoPos cs=:{cs_error={ea_loc=[top_of_stack:_]}}
+	// there is no position info, push current position to balance pop calls
+	= pushErrorAdmin top_of_stack cs
+pushErrorAdmin2 string pos=:(LinePos _ _) cs
+	= pushErrorAdmin (newPosition {id_name=string, id_info=nilPtr} pos) cs
+
+
+
+allocate_bound_var :: !FreeVar !*ExpressionHeap -> (!BoundVar, !.ExpressionHeap)
+allocate_bound_var {fv_name, fv_info_ptr} expr_heap
+	# (var_expr_ptr, expr_heap) = newPtr EI_Empty expr_heap
+	= ({ var_name = fv_name, var_info_ptr = fv_info_ptr, var_expr_ptr = var_expr_ptr }, expr_heap)
+
+
+
+allocate_free_var ident var_heap
+	# (new_var_info_ptr, var_heap) = newPtr VI_Empty var_heap
+	= ({ fv_def_level = NotALevel, fv_name = ident, fv_info_ptr = new_var_info_ptr,	fv_count = 0 }, var_heap)
+
+
+
+newVarId name = { id_name = name, id_info = nilPtr }
+
+
+
+retrieveSelectorIndexes mod_index {ste_kind = STE_Selector selector_list, ste_index, ste_previous }
+	= map (adjust_mod_index mod_index) selector_list
+where
+	adjust_mod_index mod_index selector=:{glob_module}
+		| glob_module == NoIndex
+			= { selector & glob_module = mod_index }
+			= selector
+retrieveSelectorIndexes mod_index off_kind
+	= []
+
+
+
+instance <<< FieldSymbol
+where
+	(<<<) file { fs_var } = file <<< fs_var
+
diff --git a/frontend/checksupport.dcl b/frontend/checksupport.dcl
index d355952..e52b4d2 100644
--- a/frontend/checksupport.dcl
+++ b/frontend/checksupport.dcl
@@ -134,15 +134,27 @@ instance toIdent SymbIdent, TypeSymbIdent, BoundVar, TypeVar, ATypeVar, Ident
 instance toInt STE_Kind
 instance <<< STE_Kind, IdentPos, Declaration
 
+::	ExpressionInfo =
+	{	ef_type_defs		:: !.{# CheckedTypeDef}
+	,	ef_selector_defs	:: !.{# SelectorDef}
+	,	ef_cons_defs		:: !.{# ConsDef}
+	,	ef_member_defs		:: !.{# MemberDef}
+	,	ef_class_defs		:: !.{# ClassDef}
+	,	ef_modules			:: !.{# DclModule}
+	,	ef_is_macro_fun		:: !Bool
+	}
+
+checkLocalFunctions :: !Index !Level !LocalDefs !*{#FunDef} !*ExpressionInfo !*Heaps !*CheckState
+					-> (!.{#FunDef},!.ExpressionInfo,!.Heaps,!.CheckState);
+
+convertIndex :: !Index !Index !(Optional ConversionTable) -> !Index
+
+retrieveGlobalDefinition :: !SymbolTableEntry !STE_Kind !Index -> (!Index, !Index)
 retrieveAndRemoveImportsFromSymbolTable :: ![(.a,.Declarations)] [Declaration] *(Heap SymbolTableEntry) -> ([Declaration],.Heap SymbolTableEntry);
-//retrieveAndRemoveImportsOfModuleFromSymbolTable :: ![.Declaration] ![.Declaration] ![.Declaration] !*(Heap SymbolTableEntry) -> ([Declaration],.Heap SymbolTableEntry);
-//retrieveAndRemoveImportsOfModuleFromSymbolTable :: !{!.Declaration} ![.Declaration] ![.Declaration] !*(Heap SymbolTableEntry) -> ([Declaration],.Heap SymbolTableEntry);
 addLocalFunctionDefsToSymbolTable :: !Level !Index !Index !u:{#FunDef} !*SymbolTable !*ErrorAdmin -> (!u:{# FunDef}, !*SymbolTable, !*ErrorAdmin)
 addDefToSymbolTable :: !Level !Index !Ident !STE_Kind !*SymbolTable !*ErrorAdmin -> (!* SymbolTable, !*ErrorAdmin)
-//addDeclaredSymbolsToSymbolTable :: .Bool .Int ![.Declaration] ![.Declaration] !*CheckState -> .CheckState;
 addDeclaredSymbolsToSymbolTable :: .Bool .Int ![.Declaration] !{!.Declaration} !*CheckState -> .CheckState;
 addDeclaredSymbolsToSymbolTable2 :: .Bool .Int !{!.Declaration} !{!.Declaration} !*CheckState -> .CheckState;
-//addLocalSymbolsToSymbolTable :: ![.Declaration] Int !*CheckState -> .CheckState;
 addFieldToSelectorDefinition :: !Ident (Global .Int) !*CheckState -> .CheckState;
 addGlobalDefinitionsToSymbolTable :: ![.Declaration] !*CheckState -> .CheckState;
 retrieveImportsFromSymbolTable :: ![Import ImportDeclaration] ![Declaration] !*{#DclModule} !*(Heap SymbolTableEntry) -> *(![Declaration],!*{#DclModule},!*Heap SymbolTableEntry);
@@ -151,3 +163,7 @@ removeDeclarationsFromSymbolTable :: ![Declaration] !Int !*(Heap SymbolTableEntr
 removeLocalIdentsFromSymbolTable :: .Int !.[Ident] !*(Heap SymbolTableEntry) -> .Heap SymbolTableEntry;
 removeIdentFromSymbolTable :: !.Int !Ident !*(Heap SymbolTableEntry) -> .Heap SymbolTableEntry;
 removeImportsAndLocalsOfModuleFromSymbolTable :: !Declarations !*(Heap SymbolTableEntry) -> .Heap SymbolTableEntry
+removeLocalsFromSymbolTable :: !Level ![Ident] !LocalDefs !u:{# FunDef} !*(Heap SymbolTableEntry)
+			-> (!u:{# FunDef}, !.Heap SymbolTableEntry)
+
+newFreeVariable :: !FreeVar ![FreeVar] ->(!Bool, ![FreeVar])
diff --git a/frontend/checksupport.icl b/frontend/checksupport.icl
index 394d902..22d31f3 100644
--- a/frontend/checksupport.icl
+++ b/frontend/checksupport.icl
@@ -3,6 +3,7 @@ implementation module checksupport
 import StdEnv, compare_constructor
 import syntax, predef
 import utilities
+from check import checkFunctions
 
 ::	VarHeap :== Heap VarInfo
 
@@ -206,6 +207,41 @@ where
 	envLookUp var []
 		= (False, abort "illegal value")
 
+
+::	ExpressionInfo =
+	{	ef_type_defs		:: !.{# CheckedTypeDef}
+	,	ef_selector_defs	:: !.{# SelectorDef}
+	,	ef_cons_defs		:: !.{# ConsDef}
+	,	ef_member_defs		:: !.{# MemberDef}
+	,	ef_class_defs		:: !.{# ClassDef}
+	,	ef_modules			:: !.{# DclModule}
+	,	ef_is_macro_fun		:: !Bool
+	}
+
+checkLocalFunctions :: !Index !Level !LocalDefs !*{#FunDef} !*ExpressionInfo !*Heaps !*CheckState
+					-> (!.{#FunDef},!.ExpressionInfo,!.Heaps,!.CheckState);
+checkLocalFunctions mod_index level (CollectedLocalDefs {loc_functions={ir_from,ir_to}}) fun_defs e_info heaps cs
+	= checkFunctions mod_index level ir_from ir_to fun_defs e_info heaps cs
+
+
+convertIndex :: !Index !Index !(Optional ConversionTable) -> !Index
+convertIndex index table_index (Yes tables)
+	= tables.[table_index].[index]
+convertIndex index table_index No
+	= index
+
+
+
+retrieveGlobalDefinition :: !SymbolTableEntry !STE_Kind !Index -> (!Index, !Index)
+retrieveGlobalDefinition {ste_kind = STE_Imported kind dcl_index, ste_def_level, ste_index} requ_kind mod_index
+	| kind == requ_kind
+		= (ste_index, dcl_index)
+		= (NotFound, mod_index)
+retrieveGlobalDefinition {ste_kind,ste_def_level,ste_index} requ_kind mod_index
+	| ste_kind == requ_kind && ste_def_level == cGlobalScope
+		= (ste_index, mod_index)
+		= (NotFound, mod_index)
+
 retrieveAndRemoveImportsFromSymbolTable :: ![(.a,.Declarations)] [Declaration] *(Heap SymbolTableEntry) -> ([Declaration],.Heap SymbolTableEntry);
 retrieveAndRemoveImportsFromSymbolTable [(_, {dcls_import,dcls_local,dcls_local_for_import}) : imports] all_decls symbol_table
 //	# (all_decls, symbol_table) = retrieveAndRemoveImportsOfModuleFromSymbolTable dcls_import dcls_local all_decls symbol_table
@@ -562,6 +598,38 @@ removeIdentFromSymbolTable level {id_name,id_info} symbol_table
 		= symbol_table <:= (id_info,ste_previous) // ---> ("removeIdentFromSymbolTable", id_name)
 		= symbol_table // ---> ("NO removeIdentFromSymbolTable", id_name)
 
+removeLocalsFromSymbolTable :: !Level ![Ident] !LocalDefs !u:{# FunDef} !*(Heap SymbolTableEntry)
+			-> (!u:{# FunDef}, !.Heap SymbolTableEntry)
+removeLocalsFromSymbolTable level loc_vars (CollectedLocalDefs {loc_functions={ir_from,ir_to}}) defs symbol_table
+	= remove_defs_from_symbol_table level ir_from ir_to defs (removeLocalIdentsFromSymbolTable level loc_vars symbol_table)
+where
+	remove_defs_from_symbol_table level from_index to_index defs symbol_table
+		| from_index == to_index
+			= (defs, symbol_table)	
+			#! def = defs.[from_index]
+			   id_info = (toIdent def).id_info
+			   entry = sreadPtr id_info symbol_table
+			| level == entry.ste_def_level
+				= remove_defs_from_symbol_table level (inc from_index) to_index defs (symbol_table <:= (id_info, entry.ste_previous))
+				= remove_defs_from_symbol_table level (inc from_index) to_index defs symbol_table
+
+
+newFreeVariable :: !FreeVar ![FreeVar] ->(!Bool, ![FreeVar])
+newFreeVariable new_var vars=:[free_var=:{fv_def_level,fv_info_ptr}: free_vars]
+	| new_var.fv_def_level > fv_def_level
+		= (True, [new_var : vars])
+	| new_var.fv_def_level == fv_def_level
+		| new_var.fv_info_ptr == fv_info_ptr
+			= (False, vars)
+			#! (free_var_added, free_vars) = newFreeVariable new_var free_vars
+			= (free_var_added, [free_var : free_vars])
+		#! (free_var_added, free_vars) = newFreeVariable new_var free_vars
+		= (free_var_added, [free_var : free_vars])
+newFreeVariable new_var []
+	= (True, [new_var])
+
+
+	
 class toIdent a :: !a -> Ident
 
 instance toIdent SymbIdent