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diff --git a/Sil/Util/Parser.icl b/Sil/Util/Parser.icl
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+implementation module Sil.Util.Parser
+
+import StdList
+import StdOverloaded
+
+import Control.Applicative
+import Control.Monad
+import Data.Error
+from Data.Func import $
+import Data.Functor
+import Data.List
+
+import Sil.Parse
+
+instance Functor (Parser a) where
+	fmap f m = liftM f m
+
+instance Applicative (Parser a) where
+	pure a     = Parser \i -> (Ok a, i)
+	(<*>) sf p = ap sf p
+
+instance Monad (Parser a) where
+	bind p f = Parser \i -> case runParser p i of
+		(Ok r, rest) -> runParser (f r) rest
+		(Error e, _) -> (Error e, i)
+
+instance Alternative (Parser a) where
+	empty       = Parser \i -> (Error UnknownError, i)
+	(<|>) p1 p2 = Parser \i -> case runParser p1 i of
+		(Ok r, rest)     -> (Ok r, rest)
+		(Error e1, rest) -> case runParser p2 i of
+			(Error e2, rest) -> (Error e2, i)
+			(Ok r, rest)     -> (Ok r, rest)
+
+instance name String where name s = s
+
+runParser :: (Parser a b) [a] -> (MaybeError ParseError b, [a])
+runParser (Parser f) i = f i
+
+(<?>) :: (Parser a b) ParseError -> Parser a b
+(<?>) p e = Parser \i -> case runParser p i of
+	(Error _, rest) -> (Error e, rest)
+	o               -> o
+
+fail :: Parser a b
+fail = empty
+
+top :: Parser a a
+top = Parser \i -> case i of
+	[]     = (Error UnknownError, [])
+	[x:xs] = (Ok x, xs)
+
+peek :: Parser a a
+peek = Parser \i -> case i of
+	[]     = (Error UnknownError, [])
+	[x:xs] = (Ok x, [x:xs])
+
+satisfy :: (a -> Bool) -> Parser a a
+satisfy f = top >>= \r -> if (f r) (pure r) fail
+
+check :: (a -> Bool) -> Parser a a
+check f = peek >>= \r -> if (f r) (pure r) fail
+
+(until) infix 2 :: (Parser a b) (Parser a c) -> Parser a [b]
+(until) p guard = try $ until` p guard [] 
+where
+	until` :: (Parser a b) (Parser a c) [b] -> Parser a [b]
+	until` p guard acc = Parser \i -> case runParser guard i of
+		(Ok _, rest) -> (Ok acc, rest)
+		(Error _, _) -> case runParser p i of
+			(Ok r, rest) -> runParser (until` p guard [r:acc]) rest
+			(Error e, _) -> (Error e, i)
+
+	try :: (Parser a b) -> Parser a b
+	try p = Parser \i -> case runParser p i of
+		(Error e, _) -> (Error e, i)
+		(Ok r, rest) -> (Ok r, rest)
+
+item :: a -> Parser a a | ==, name a
+item a  = satisfy ((==) a) <?> Expected (name a)
+
+list :: [a] -> Parser a [a] | ==, name a
+list as = mapM item as
+
+seplist :: a (Parser a b) -> Parser a [b] | ==, name a
+seplist sep p = liftM2 (\es e-> es ++ [e]) (some (p <* item sep)) p
+	<|> liftM pure p
+	<|> pure empty
+
+eof :: Parser a ()
+eof = Parser \i -> case i of
+	[] = (Ok (), [])
+	_  = (Error $ Expected "eof", i)