The final batch of changes for the new coercion representation

[ghc-hetmet.git] / compiler / typecheck / TcRnDriver.lhs

diff --git a/compiler/typecheck/TcRnDriver.lhs b/compiler/typecheck/TcRnDriver.lhs
index e2c79ee..b6525b8 100644 (file)
--- a/compiler/typecheck/TcRnDriver.lhs
+++ b/compiler/typecheck/TcRnDriver.lhs
@@ -72,7 +72,6 @@ import Outputable
 import DataCon
 import Type
 import Class
-import Pair
 import TcType   ( orphNamesOfDFunHead )
 import Inst    ( tcGetInstEnvs )
 import Data.List ( sortBy )
@@ -1195,7 +1194,7 @@ runPlans (p:ps) = tryTcLIE_ (runPlans ps) p
 
 --------------------
 mkPlan :: LStmt Name -> TcM PlanResult
-mkPlan (L loc (ExprStmt expr _ _))     -- An expression typed at the prompt 
+mkPlan (L loc (ExprStmt expr _ _ _))   -- An expression typed at the prompt 
   = do { uniq <- newUnique             -- is treated very specially
        ; let fresh_it  = itName uniq
              the_bind  = L loc $ mkFunBind (L loc fresh_it) matches
@@ -1204,7 +1203,7 @@ mkPlan (L loc (ExprStmt expr _ _))        -- An expression typed at the prompt
              bind_stmt = L loc $ BindStmt (nlVarPat fresh_it) expr
                                           (HsVar bindIOName) noSyntaxExpr 
              print_it  = L loc $ ExprStmt (nlHsApp (nlHsVar printName) (nlHsVar fresh_it))
-                                          (HsVar thenIOName) placeHolderType
+                                          (HsVar thenIOName) noSyntaxExpr placeHolderType
 
        -- The plans are:
        --      [it <- e; print it]     but not if it::()
@@ -1232,7 +1231,7 @@ mkPlan (L loc (ExprStmt expr _ _))        -- An expression typed at the prompt
 mkPlan stmt@(L loc (BindStmt {}))
   | [v] <- collectLStmtBinders stmt            -- One binder, for a bind stmt 
   = do { let print_v  = L loc $ ExprStmt (nlHsApp (nlHsVar printName) (nlHsVar v))
-                                          (HsVar thenIOName) placeHolderType
+                                         (HsVar thenIOName) noSyntaxExpr placeHolderType
 
        ; print_bind_result <- doptM Opt_PrintBindResult
        ; let print_plan = do
@@ -1259,11 +1258,25 @@ tcGhciStmts stmts
        let {
            ret_ty    = mkListTy unitTy ;
            io_ret_ty = mkTyConApp ioTyCon [ret_ty] ;
-           tc_io_stmts stmts = tcStmts GhciStmt tcDoStmt stmts io_ret_ty ;
-
+           tc_io_stmts stmts = tcStmtsAndThen GhciStmt tcDoStmt stmts io_ret_ty ;
            names = collectLStmtsBinders stmts ;
+        } ;
+
+       -- OK, we're ready to typecheck the stmts
+       traceTc "TcRnDriver.tcGhciStmts: tc stmts" empty ;
+       ((tc_stmts, ids), lie) <- captureConstraints $ 
+                                  tc_io_stmts stmts  $ \ _ ->
+                                 mapM tcLookupId names  ;
+                       -- Look up the names right in the middle,
+                       -- where they will all be in scope
+
+       -- Simplify the context
+       traceTc "TcRnDriver.tcGhciStmts: simplify ctxt" empty ;
+       const_binds <- checkNoErrs (simplifyInteractive lie) ;
+               -- checkNoErrs ensures that the plan fails if context redn fails
 
-               -- mk_return builds the expression
+       traceTc "TcRnDriver.tcGhciStmts: done" empty ;
+        let {   -- mk_return builds the expression
                --      returnIO @ [()] [coerce () x, ..,  coerce () z]
                --
                -- Despite the inconvenience of building the type applications etc,
@@ -1274,27 +1287,14 @@ tcGhciStmts stmts
                -- then the type checker would instantiate x..z, and we wouldn't
                -- get their *polymorphic* values.  (And we'd get ambiguity errs
                -- if they were overloaded, since they aren't applied to anything.)
-           mk_return ids = nlHsApp (nlHsTyApp ret_id [ret_ty]) 
-                                   (noLoc $ ExplicitList unitTy (map mk_item ids)) ;
+           ret_expr = nlHsApp (nlHsTyApp ret_id [ret_ty]) 
+                      (noLoc $ ExplicitList unitTy (map mk_item ids)) ;
            mk_item id = nlHsApp (nlHsTyApp unsafeCoerceId [idType id, unitTy])
-                                (nlHsVar id) 
-        } ;
-
-       -- OK, we're ready to typecheck the stmts
-       traceTc "TcRnDriver.tcGhciStmts: tc stmts" empty ;
-       ((tc_stmts, ids), lie) <- captureConstraints $ tc_io_stmts stmts $ \ _ ->
-                                          mapM tcLookupId names ;
-                                       -- Look up the names right in the middle,
-                                       -- where they will all be in scope
-
-       -- Simplify the context
-       traceTc "TcRnDriver.tcGhciStmts: simplify ctxt" empty ;
-       const_binds <- checkNoErrs (simplifyInteractive lie) ;
-               -- checkNoErrs ensures that the plan fails if context redn fails
-
-       traceTc "TcRnDriver.tcGhciStmts: done" empty ;
+                                (nlHsVar id) ;
+           stmts = tc_stmts ++ [noLoc (mkLastStmt ret_expr)]
+        } ;
        return (ids, mkHsDictLet (EvBinds const_binds) $
-                    noLoc (HsDo GhciStmt tc_stmts (mk_return ids) io_ret_ty))
+                    noLoc (HsDo GhciStmt stmts io_ret_ty))
     }
 \end{code}
 
@@ -1611,7 +1611,7 @@ ppr_tycons fam_insts type_env
   = vcat [ text "TYPE CONSTRUCTORS"
          ,   nest 2 (ppr_tydecls tycons)
          , text "COERCION AXIOMS" 
-         ,   nest 2 (ppr_axioms (typeEnvCoAxioms type_env)) ]
+         ,   nest 2 (vcat (map pprCoAxiom (typeEnvCoAxioms type_env))) ]
   where
     fi_tycons = map famInstTyCon fam_insts
     tycons = [tycon | tycon <- typeEnvTyCons type_env, want_tycon tycon]
@@ -1646,14 +1646,6 @@ ppr_tydecls tycons
     ppr_tycon tycon = ppr (tyThingToIfaceDecl (ATyCon tycon))
       where
 
-ppr_axioms :: [CoAxiom] -> SDoc
-ppr_axioms axs
-  = vcat (map ppr_ax axs)
-  where
-    ppr_ax ax = sep [ ptext (sLit "coercion") <+> ppr ax <+> ppr (co_ax_tvs ax)
-                    , nest 2 (dcolon <+> pprEqPred 
-                                           (Pair (co_ax_lhs ax) (co_ax_rhs ax))) ]
-
 ppr_rules :: [CoreRule] -> SDoc
 ppr_rules [] = empty
 ppr_rules rs = vcat [ptext (sLit "{-# RULES"),