Changeset 9480

Timestamp:

03/13/06 11:17:08 (3 years ago)

Author:

audreyt

Message:

* fix overeager inferencer in simple array/hash indexing;

it was evaluating them in the current context, and if it's lvalue,
then the element could get autovivified.
rindolf++ for reporting the bug; t/pugsbugs/short_circuiting.t now passes.

Location:

src/Pugs

Files:

• Eval.hs (modified) (1 diff)
• Eval/Var.hs (modified) (1 diff)
• Monads.hs (modified) (2 diffs)

src/Pugs/Eval.hs

@@ -176 +176 @@
     VControl c      -> retControl c
     _               -> action
-
-{-|
-Perform the given evaluation in an /LValue/ context.
--}
-enterLValue :: Eval a -> Eval a
-enterLValue = local (\e -> e{ envLValue = True })
-{-|
-Perform the given evaluation in an /RValue/ (i.e. non-/LValue/) context.
--}
-enterRValue :: Eval a -> Eval a
-enterRValue = local (\e -> e{ envLValue = False })
-
-
 
 evalRef :: VRef -> Eval Val

src/Pugs/Eval/Var.hs

@@ -376 +376 @@
 inferExpType (Syn "=>" _)   = return $ mkType "Pair"
 inferExpType exp@(Syn "{}" [_, idxExp]) = if isSimpleExp exp
-    then fromVal =<< evalExp exp
+    then fromVal =<< enterRValue (evalExp exp)
     else fmap typeOfCxt (inferExpCxt idxExp)
 inferExpType exp@(Syn "[]" [_, idxExp]) = if isSimpleExp exp
-    then fromVal =<< evalExp exp
+    then fromVal =<< enterRValue (evalExp exp)
     else fmap typeOfCxt (inferExpCxt idxExp)
 inferExpType (Syn "sub" [exp]) = inferExpType exp

src/Pugs/Monads.hs

@@ -14 +14 @@
 
 module Pugs.Monads (
+    enterLValue, enterRValue,
     enterLex, enterContext, enterEvalContext, enterPackage, enterCaller,
     enterGiven, enterWhen, enterWhile, genSymPrim, genSymCC,
@@ -47 +48 @@
         return $ ma `mplus` mb
 
+{-|
+Perform the given evaluation in an /LValue/ context.
+-}
+enterLValue :: Eval a -> Eval a
+enterLValue = local (\e -> e{ envLValue = True })
+{-|
+Perform the given evaluation in an /RValue/ (i.e. non-/LValue/) context.
+-}
+enterRValue :: Eval a -> Eval a
+enterRValue = local (\e -> e{ envLValue = False })
 
 {-|