Repository : ssh://darcs.haskell.org//srv/darcs/ghc On branch : type-nats
http://hackage.haskell.org/trac/ghc/changeset/f200e2e413d83c900ac26304bf90dbcd2e4e05a1 >--------------------------------------------------------------- commit f200e2e413d83c900ac26304bf90dbcd2e4e05a1 Author: Iavor S. Diatchki <iavor.diatc...@gmail.com> Date: Tue Dec 25 11:43:51 2012 -0800 Add the second half of the rules for subtraction (SubE/SubI). >--------------------------------------------------------------- compiler/typecheck/TcTypeNatsRules.hs | 7 ++++++- 1 files changed, 6 insertions(+), 1 deletions(-) diff --git a/compiler/typecheck/TcTypeNatsRules.hs b/compiler/typecheck/TcTypeNatsRules.hs index 1fa255e..ffde1b9 100644 --- a/compiler/typecheck/TcTypeNatsRules.hs +++ b/compiler/typecheck/TcTypeNatsRules.hs @@ -219,6 +219,7 @@ widenRules = [ n2 <== a, mkExp a b === c ] (b <== c)) + -- Improvements related to `FromNat1` , (True, mkAx 60 "FromNat1_inj" (take 2 nat1Vars ++ take 1 (drop 2 natVars)) [ mkFromNat1 a1 === c, mkFromNat1 b1 === c] (a1 === b1)) @@ -239,6 +240,10 @@ widenRules = Currently this is implemented with some hand-written code in TcTypeNats.hs -} + -- Desugaring rules for `iff` rules, forward direction. + , (True, mkAx 66 "SubE" (take 3 natVars) + [ mkSub c b === a ] (mkAdd a b === c)) + ] where a : b : c : x : y : z : _ = map mkTyVarTy natVars @@ -249,7 +254,7 @@ widenRules = iffRules :: [CoAxiomRule] iffRules = - [ mkAx 65 "SubDef" (take 3 natVars) [ mkAdd a b === c ] (mkSub c b === a) + [ mkAx 65 "SubI" (take 3 natVars) [ mkAdd a b === c ] (mkSub c b === a) ] where a : b : c : _ = map mkTyVarTy natVars _______________________________________________ Cvs-ghc mailing list Cvs-ghc@haskell.org http://www.haskell.org/mailman/listinfo/cvs-ghc
