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Properly quantify variables in Data expressions.

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This commit is contained in:
Evan Czaplicki 2013-08-12 01:09:26 -07:00
parent 585107eaed
commit a736a28a43
1 changed files with 3 additions and 5 deletions
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8
compiler/Type/Constrain/Expression.hs
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@ -86,13 +86,11 @@ constrain env (L span expr) tipe =
and . (:) ce <$> mapM branch branches and . (:) ce <$> mapM branch branches
Data name exprs -> Data name exprs ->
do pairs <- mapM pair exprs do vars <- forM exprs $ \_ -> var Flexible
let pairs = zip exprs (map VarN vars)
(ctipe, cs) <- Monad.foldM step (tipe,true) (reverse pairs) (ctipe, cs) <- Monad.foldM step (tipe,true) (reverse pairs)
return (cs /\ name <? ctipe) return $ ex vars (cs /\ name <? ctipe)
where where
pair e = do v <- var Flexible -- needs an ex
return (e, VarN v)
step (t,c) (e,x) = do step (t,c) (e,x) = do
c' <- constrain env e x c' <- constrain env e x
return (x ==> t, c /\ c') return (x ==> t, c /\ c')