[commit: ghc] wip/T15809: Start to eliminate tcFamTyPats (584cdfc)

[git at git.haskell.org]

Repository : ssh://git@git.haskell.org/ghc

On branch  : wip/T15809
Link       : http://ghc.haskell.org/trac/ghc/changeset/584cdfc05568d8a2ea6864df81bdcdaf9f87465b/ghc

>---------------------------------------------------------------

commit 584cdfc05568d8a2ea6864df81bdcdaf9f87465b
Author: Simon Peyton Jones <simonpj at microsoft.com>
Date:   Mon Nov 12 13:41:33 2018 +0000

    Start to eliminate tcFamTyPats


>---------------------------------------------------------------

584cdfc05568d8a2ea6864df81bdcdaf9f87465b
 compiler/typecheck/TcHsType.hs     |  1 +
 compiler/typecheck/TcTyClsDecls.hs | 20 ++++++++------------
 2 files changed, 9 insertions(+), 12 deletions(-)

diff --git a/compiler/typecheck/TcHsType.hs b/compiler/typecheck/TcHsType.hs
index 7f637b7..fe8c1a0 100644
--- a/compiler/typecheck/TcHsType.hs
+++ b/compiler/typecheck/TcHsType.hs
@@ -21,6 +21,7 @@ module TcHsType (
         UserTypeCtxt(..),
         bindImplicitTKBndrs_Skol, bindImplicitTKBndrs_Q_Skol,
         bindExplicitTKBndrs_Skol, bindExplicitTKBndrs_Q_Skol,
+        ContextKind(..),
 
                 -- Type checking type and class decls
         kcLookupTcTyCon, kcTyClTyVars, tcTyClTyVars,
diff --git a/compiler/typecheck/TcTyClsDecls.hs b/compiler/typecheck/TcTyClsDecls.hs
index 5b5d858..b9227de 100644
--- a/compiler/typecheck/TcTyClsDecls.hs
+++ b/compiler/typecheck/TcTyClsDecls.hs
@@ -1760,6 +1760,7 @@ tcTyFamInstEqn :: TcTyCon -> Maybe ClsInstInfo -> LTyFamInstEqn GhcRn
 -- (typechecked here) have TyFamInstEqns
 
 
+{-
 tcTyFamInstEqn fam_tc mb_clsinfo
     (L loc (HsIB { hsib_ext = imp_vars
                  , hsib_body = FamEqn { feqn_tycon  = L _ eqn_tc_name
@@ -1780,8 +1781,8 @@ tcTyFamInstEqn fam_tc mb_clsinfo
        ; return (mkCoAxBranch tvs' [] pats' rhs_ty'
                               (map (const Nominal) tvs')
                               loc) }
+-}
 
-{-
 tcTyFamInstEqn fam_tc mb_clsinfo
     eqn@(L loc (HsIB { hsib_ext = imp_vars
                  , hsib_body = FamEqn { feqn_tycon  = L _ eqn_tc_name
@@ -1790,12 +1791,12 @@ tcTyFamInstEqn fam_tc mb_clsinfo
                                       , feqn_rhs    = hs_ty }}))
   = ASSERT( getName fam_tc == eqn_tc_name )
     setSrcSpan loc $
-    do { traceTc "tcTyFamInstEqn {" (ppr eqn)
-       ; (imp_tvs, (exp_tvs, ((pats, rhs_ty))))
+    do { traceTc "tcTyFamInstEqn {" (ppr eqn_tc_name <+> ppr hs_pats)
+       ; (_imp_tvs, (_exp_tvs, ((pats, rhs_ty))))
            <- pushTcLevelM_                     $
               solveEqualities                   $
               bindImplicitTKBndrs_Q_Skol imp_vars $
-              bindExplicitTKBndrs_Q_Skol (mb_expl_bndrs `orElse` []) $
+              bindExplicitTKBndrs_Q_Skol AnyKind (mb_expl_bndrs `orElse` []) $
               do { let fam_name  = tyConName fam_tc
                        lhs_fun = L loc (HsTyVar noExt NotPromoted
                                                 (L loc fam_name))
@@ -1808,21 +1809,16 @@ tcTyFamInstEqn fam_tc mb_clsinfo
                   ; rhs_ty <- tcCheckLHsType hs_ty res_kind
                   ; return (pats, rhs_ty) }
 
-       ; imp_tvs <- zonkAndScopedSort imp_tvs
-       ; let spec_req_tkvs = imp_tvs ++ exp_tvs
-       ; dvs <- candidateQTyVarsOfKinds $
-                typeKind rhs_ty : map tyVarKind (spec_req_tkvs)
-       ; let final_dvs = dvs `delCandidates` spec_req_tkvs
-       ; inferred_kvs <- quantifyTyVars emptyVarSet final_dvs
+       ; dvs <- candidateQTyVarsOfTypes (rhs_ty : pats)
+       ; qtkvs <- quantifyTyVars emptyVarSet dvs
 
-       ; (ze, tvs') <- zonkTyBndrs (inferred_kvs ++ spec_req_tkvs)
+       ; (ze, tvs') <- zonkTyBndrs qtkvs
        ; pats'      <- zonkTcTypesToTypesX ze pats
        ; rhs_ty'    <- zonkTcTypeToTypeX ze rhs_ty
        ; traceTc "tcTyFamInstEqn }" (ppr fam_tc <+> pprTyVars tvs')
        ; return (mkCoAxBranch tvs' [] pats' rhs_ty'
                               (map (const Nominal) tvs')
                               loc) }
--}
 
 
 tcTyFamInstEqn _ _ (L _ (XHsImplicitBndrs _)) = panic "tcTyFamInstEqn"