FIX #4825: Update User Guide info on DLLs.

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

diff --git a/compiler/typecheck/TcSMonad.lhs b/compiler/typecheck/TcSMonad.lhs
index 87cd5eb..b2ce381 100644 (file)
--- a/compiler/typecheck/TcSMonad.lhs
+++ b/compiler/typecheck/TcSMonad.lhs
@@ -82,6 +82,7 @@ import qualified TcRnMonad as TcM
 import qualified TcMType as TcM
 import qualified TcEnv as TcM 
        ( checkWellStaged, topIdLvl, tcLookupFamInst, tcGetDefaultTys )
+import Kind
 import TcType
 import DynFlags
 
@@ -97,14 +98,18 @@ import Outputable
 import Bag
 import MonadUtils
 import VarSet
+import Pair
 import FastString
 
 import HsBinds               -- for TcEvBinds stuff 
 import Id 
-
 import TcRnTypes
-
 import Data.IORef
+
+#ifdef DEBUG
+import StaticFlags( opt_PprStyle_Debug )
+import Control.Monad( when )
+#endif
 \end{code}
 
 
@@ -204,9 +209,9 @@ instance Outputable CanonicalCt where
   ppr (CIPCan ip fl ip_nm ty)     
       = ppr fl <+> ppr ip <+> dcolon <+> parens (ppr ip_nm <> dcolon <> ppr ty)
   ppr (CTyEqCan co fl tv ty)      
-      = ppr fl <+> ppr co <+> dcolon <+> pprEqPred (mkTyVarTy tv, ty)
+      = ppr fl <+> ppr co <+> dcolon <+> pprEqPred (Pair (mkTyVarTy tv) ty)
   ppr (CFunEqCan co fl tc tys ty) 
-      = ppr fl <+> ppr co <+> dcolon <+> pprEqPred (mkTyConApp tc tys, ty)
+      = ppr fl <+> ppr co <+> dcolon <+> pprEqPred (Pair (mkTyConApp tc tys) ty)
   ppr (CFrozenErr co fl)
       = ppr fl <+> pprEvVarWithType co
 \end{code}
@@ -421,17 +426,16 @@ type TcsUntouchables = (Untouchables,TcTyVarSet)
 
 \begin{code}
 data SimplContext
-  = SimplInfer         -- Inferring type of a let-bound thing
-  | SimplRuleLhs       -- Inferring type of a RULE lhs
-  | SimplInteractive   -- Inferring type at GHCi prompt
-  | SimplCheck         -- Checking a type signature or RULE rhs
-  deriving Eq
+  = SimplInfer SDoc       -- Inferring type of a let-bound thing
+  | SimplRuleLhs RuleName  -- Inferring type of a RULE lhs
+  | SimplInteractive      -- Inferring type at GHCi prompt
+  | SimplCheck SDoc       -- Checking a type signature or RULE rhs
 
 instance Outputable SimplContext where
-  ppr SimplInfer       = ptext (sLit "SimplInfer")
-  ppr SimplRuleLhs     = ptext (sLit "SimplRuleLhs")
+  ppr (SimplInfer d)   = ptext (sLit "SimplInfer") <+> d
+  ppr (SimplCheck d)   = ptext (sLit "SimplCheck") <+> d
+  ppr (SimplRuleLhs n) = ptext (sLit "SimplRuleLhs") <+> doubleQuotes (ftext n)
   ppr SimplInteractive = ptext (sLit "SimplInteractive")
-  ppr SimplCheck       = ptext (sLit "SimplCheck")
 
 isInteractive :: SimplContext -> Bool
 isInteractive SimplInteractive = True
@@ -441,14 +445,14 @@ simplEqsOnly :: SimplContext -> Bool
 -- Simplify equalities only, not dictionaries
 -- This is used for the LHS of rules; ee
 -- Note [Simplifying RULE lhs constraints] in TcSimplify
-simplEqsOnly SimplRuleLhs = True
-simplEqsOnly _            = False
+simplEqsOnly (SimplRuleLhs {}) = True
+simplEqsOnly _                 = False
 
 performDefaulting :: SimplContext -> Bool
-performDefaulting SimplInfer              = False
-performDefaulting SimplRuleLhs            = False
-performDefaulting SimplInteractive = True
-performDefaulting SimplCheck       = True
+performDefaulting (SimplInfer {})   = False
+performDefaulting (SimplRuleLhs {}) = False
+performDefaulting SimplInteractive  = True
+performDefaulting (SimplCheck {})   = True
 
 ---------------
 newtype TcS a = TcS { unTcS :: TcSEnv -> TcM a } 
@@ -526,7 +530,9 @@ runTcS context untouch tcs
 
 #ifdef DEBUG
        ; count <- TcM.readTcRef step_count
-       ; TcM.dumpTcRn (ptext (sLit "Constraint solver steps =") <+> int count)
+       ; when (opt_PprStyle_Debug && count > 0) $
+         TcM.debugDumpTcRn (ptext (sLit "Constraint solver steps =") 
+                            <+> int count <+> ppr context)
 #endif
              -- And return
        ; ev_binds      <- TcM.readTcRef evb_ref
@@ -563,8 +569,9 @@ recoverTcS (TcS recovery_code) (TcS thing_inside)
 
 ctxtUnderImplic :: SimplContext -> SimplContext
 -- See Note [Simplifying RULE lhs constraints] in TcSimplify
-ctxtUnderImplic SimplRuleLhs = SimplCheck
-ctxtUnderImplic ctxt         = ctxt
+ctxtUnderImplic (SimplRuleLhs n) = SimplCheck (ptext (sLit "lhs of rule") 
+                                               <+> doubleQuotes (ftext n))
+ctxtUnderImplic ctxt              = ctxt
 
 tryTcS :: TcS a -> TcS a
 -- Like runTcS, but from within the TcS monad 
@@ -672,7 +679,7 @@ checkWellStagedDFun pred dfun_id loc
     bind_lvl = TcM.topIdLvl dfun_id
 
 pprEq :: TcType -> TcType -> SDoc
-pprEq ty1 ty2 = pprPred $ mkEqPred (ty1,ty2)
+pprEq ty1 ty2 = pprPredTy $ mkEqPred (ty1,ty2)
 
 isTouchableMetaTyVar :: TcTyVar -> TcS Bool
 isTouchableMetaTyVar tv