diff options
Diffstat (limited to 'sucl/spine.dcl')
| -rw-r--r-- | sucl/spine.dcl | 17 |
1 files changed, 15 insertions, 2 deletions
diff --git a/sucl/spine.dcl b/sucl/spine.dcl index fb7b784..f45a0f5 100644 --- a/sucl/spine.dcl +++ b/sucl/spine.dcl @@ -2,9 +2,12 @@ definition module spine // $Id$ +from history import History,HistoryAssociation,HistoryPattern from rule import Rgraph,Rule +from graph import Graph from pfun import Pfun from general import Optional +from StdOverloaded import == /* @@ -163,7 +166,7 @@ in a graph. | MissingCase // All alternatives failed for a function symbol | Open (Rgraph sym pvar) // Need root normal form of open node for matching | Partial (Rule sym pvar) (Pfun pvar var) pvar (Spine sym var pvar) // A rule was strictly partially matched - | Unsafe (Rgraph sym var) // Terminated due to immininent recursion + | Unsafe (HistoryPattern sym var) // Terminated due to immininent recursion | Redex (Rule sym pvar) (Pfun pvar var) // Total match | Strict // Need root normal form due to strictness @@ -176,7 +179,7 @@ foldspine .subresult // Fold a MissingCase subspine ((Rgraph sym pvar) -> .subresult) // Fold an Open subspine ((Rule sym pvar) (Pfun pvar var) pvar .result -> .subresult) // Fold a Partial subspine - ((Rgraph sym var) -> .subresult) // Fold an Unsafe subspine + ((HistoryPattern sym var) -> .subresult) // Fold an Unsafe subspine ((Rule sym pvar) (Pfun pvar var) -> .subresult) // Fold a Redex subspine .subresult // Fold a Strict subspine .(Spine sym var pvar) // The spine to fold @@ -193,3 +196,13 @@ spinenodes :: .(Spine sym var pvar) -> [var] // Make a decision (continuation based) on whether a spine ends in Open ifopen :: result result !.(Answer sym var pvar) -> result + +// Extend the history according to a spine +extendhistory + :: (Graph sym var) // Subject graph + (Spine sym var pvar) // Spine leading to the reduction operation + (History sym var) // Old history + -> History sym var // New history + | == sym + & == var + & == pvar |