compile cuts

app/Compiler.hs

@@ -36,11 +36,13 @@ variablizePrlg void vs (LiteralI i)
   | Just idx <- elemIndex i vs = VarI idx i
   | otherwise = LiteralI i
 
-compileGoals :: Id -> PrlgInt -> [Code]
+compileGoals :: Id -> Int -> PrlgInt -> [Code]
-compileGoals andop = go
+compileGoals andop cut = go
   where
     go p@(CallI x args)
       | x == andop = concatMap go args
+    go p@(LiteralI x)
+      | x == cut = [[Cut]]
     go x = [compileGoal x]
 
 compileGoal :: PrlgInt -> Code
@@ -58,4 +60,5 @@ seqGoals [] = [NoGoal]
 seqGoals [[Cut]] = [Cut, NoGoal]
 seqGoals [x] = [Goal] ++ x ++ [LastCall]
 seqGoals [x, [Cut]] = [Goal] ++ x ++ [LastCall, Cut]
+seqGoals ([Cut]:xs) = [Cut] ++ seqGoals xs
 seqGoals (x:xs) = [Goal] ++ x ++ [Call] ++ seqGoals xs

app/Frontend.hs

@@ -53,8 +53,8 @@ interpret = (>> return True) . lex
       compile prlgv
     compile prlgv = do
       commaId <- findStruct "," 2
-      -- TODO cut
+      cut <- findAtom "!"
-      let code = C.seqGoals $ C.compileGoals commaId prlgv
+      let code = C.seqGoals $ C.compileGoals commaId cut prlgv
       execute code
     execute code = do
       res <- I.prove code
@@ -73,7 +73,7 @@ interpreterStart = do
 
 interpreterLoop :: PrlgEnv ()
 interpreterLoop = do
-  minput <- lift $ getInputLine "π> "
+  minput <- lift $ getInputLine "prlg> "
   case minput of
     Nothing -> return ()
     Just input -> do