diff options
Diffstat (limited to 'compiler/GHC/Tc/Utils/Instantiate.hs')
| -rw-r--r-- | compiler/GHC/Tc/Utils/Instantiate.hs | 18 |
1 files changed, 12 insertions, 6 deletions
diff --git a/compiler/GHC/Tc/Utils/Instantiate.hs b/compiler/GHC/Tc/Utils/Instantiate.hs index e7e5c9dc09..e72e5742a6 100644 --- a/compiler/GHC/Tc/Utils/Instantiate.hs +++ b/compiler/GHC/Tc/Utils/Instantiate.hs @@ -16,7 +16,7 @@ module GHC.Tc.Utils.Instantiate ( instCall, instDFunType, instStupidTheta, instTyVarsWith, newWanted, newWanteds, - tcInstInvisibleTyBinders, tcInstInvisibleTyBinder, + tcInstInvisibleTyBindersN, tcInstInvisibleTyBinders, tcInstInvisibleTyBinder, newOverloadedLit, mkOverLit, @@ -366,13 +366,19 @@ instStupidTheta orig theta * * ********************************************************************* -} --- | Instantiates up to n invisible binders --- Returns the instantiating types, and body kind -tcInstInvisibleTyBinders :: Int -> TcKind -> TcM ([TcType], TcKind) +-- | Given ty::forall k1 k2. k, instantiate all the invisible forall-binders +-- returning ty @kk1 @kk2 :: k[kk1/k1, kk2/k1] +tcInstInvisibleTyBinders :: TcType -> TcKind -> TcM (TcType, TcKind) +tcInstInvisibleTyBinders ty kind + = do { (extra_args, kind') <- tcInstInvisibleTyBindersN n_invis kind + ; return (mkAppTys ty extra_args, kind') } + where + n_invis = invisibleTyBndrCount kind -tcInstInvisibleTyBinders 0 kind +tcInstInvisibleTyBindersN :: Int -> TcKind -> TcM ([TcType], TcKind) +tcInstInvisibleTyBindersN 0 kind = return ([], kind) -tcInstInvisibleTyBinders n ty +tcInstInvisibleTyBindersN n ty = go n empty_subst ty where empty_subst = mkEmptyTCvSubst (mkInScopeSet (tyCoVarsOfType ty)) |