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| author | krasimir <krasimir@chalmers.se> | 2009-01-20 14:33:42 +0000 |
|---|---|---|
| committer | krasimir <krasimir@chalmers.se> | 2009-01-20 14:33:42 +0000 |
| commit | e3892b82c0f1a73ce529dbfde2a2753475c94355 (patch) | |
| tree | d72d12352e2d5ebf323297cf66792c2042fa239b /src/GF/Grammar/Unify.hs | |
| parent | d6e917b5a1454bc75226d27ed71171b2617a4d46 (diff) | |
remove some dead types from GF.Grammar.Grammar
Diffstat (limited to 'src/GF/Grammar/Unify.hs')
| -rw-r--r-- | src/GF/Grammar/Unify.hs | 14 |
1 files changed, 7 insertions, 7 deletions
diff --git a/src/GF/Grammar/Unify.hs b/src/GF/Grammar/Unify.hs index 588c1b306..58c0e37fd 100644 --- a/src/GF/Grammar/Unify.hs +++ b/src/GF/Grammar/Unify.hs @@ -38,8 +38,8 @@ unifyVal cs0 = do (_,VClos (_:_) _) -> True _ -> False -type Unifier = [(MetaSymb, Trm)] -type Constrs = [(Trm, Trm)] +type Unifier = [(MetaSymb, Term)] +type Constrs = [(Term, Term)] unifyAll :: Constrs -> Unifier -> (Unifier,Constrs) unifyAll [] g = (g, []) @@ -49,7 +49,7 @@ unifyAll ((a@(s, t)) : l) g = Ok g2 -> (g2, c) _ -> (g1, a : c) -unify :: Trm -> Trm -> Unifier -> Err Unifier +unify :: Term -> Term -> Unifier -> Err Unifier unify e1 e2 g = case (e1, e2) of (Meta s, t) -> do @@ -67,12 +67,12 @@ unify e1 e2 g = _ -> prtBad "fail unify" e1 _ -> prtBad "fail unify" e1 -extend :: Unifier -> MetaSymb -> Trm -> Err Unifier +extend :: Unifier -> MetaSymb -> Term -> Err Unifier extend g s t | (t == Meta s) = return g | occCheck s t = prtBad "occurs check" t | True = return ((s, t) : g) -subst_all :: Unifier -> Trm -> Err Trm +subst_all :: Unifier -> Term -> Err Term subst_all s u = case (s,u) of ([], t) -> return t @@ -80,14 +80,14 @@ subst_all s u = t' <- (subst_all l t) --- successive substs - why ? return $ substMetas [a] t' -substMetas :: [(MetaSymb,Trm)] -> Trm -> Trm +substMetas :: [(MetaSymb,Term)] -> Term -> Term substMetas subst trm = case trm of Meta x -> case lookup x subst of Just t -> t _ -> trm _ -> composSafeOp (substMetas subst) trm -occCheck :: MetaSymb -> Trm -> Bool +occCheck :: MetaSymb -> Term -> Bool occCheck s u = case u of Meta v -> s == v App c a -> occCheck s c || occCheck s a |