From 5faabaf240316300e48cf37eae0d5e2bfd0ec66c Mon Sep 17 00:00:00 2001 From: Jed Barber Date: Tue, 29 May 2012 07:30:50 +1000 Subject: All potential errors now caught into Nothings --- Term.hs | 9 +-------- 1 file changed, 1 insertion(+), 8 deletions(-) (limited to 'Term.hs') diff --git a/Term.hs b/Term.hs index 23fc5c5..dfcf1cf 100644 --- a/Term.hs +++ b/Term.hs @@ -2,8 +2,6 @@ module Term ( Term(..), Substitution, - nullTerm, - alphaEquiv, alphaConvert, alphaConvertList, @@ -34,8 +32,7 @@ data Term = TVar { tVar :: Var } | TApp { tAppLeft :: Term , tAppRight :: Term } | TAbs { tAbsVar :: Term - , tAbsTerm :: Term } - | TNull deriving (Ord) + , tAbsTerm :: Term } deriving (Ord) type Substitution = ( [(Name,Type)], [(Var,Term)] ) @@ -54,10 +51,6 @@ instance Eq Term where -nullTerm :: Term -nullTerm = TNull - - alphaEquiv :: Term -> Term -> Bool alphaEquiv a b = let equiv = \term1 term2 varmap1 varmap2 depth -> -- cgit