ATs are now implicitTyThings

[ghc-hetmet.git] / compiler / iface / LoadIface.lhs

diff --git a/compiler/iface/LoadIface.lhs b/compiler/iface/LoadIface.lhs
index f76fa78..21332fa 100644 (file)
--- a/compiler/iface/LoadIface.lhs
+++ b/compiler/iface/LoadIface.lhs
@@ -35,6 +35,8 @@ import HscTypes               ( ModIface(..), TyThing, IfaceExport, Usage(..),
 import BasicTypes      ( Version, initialVersion,
                          Fixity(..), FixityDirection(..), isMarkedStrict )
 import TcRnMonad
+import Type             ( TyThing(..) )
+import Class           ( classATs )
 
 import PrelNames       ( gHC_PRIM )
 import PrelInfo                ( ghcPrimExports )
@@ -47,9 +49,9 @@ import NameEnv
 import MkId            ( seqId )
 import Module
 import OccName         ( OccName, mkOccEnv, lookupOccEnv, mkClassTyConOcc,
-                          mkClassDataConOcc, mkSuperDictSelOcc,
-                          mkDataConWrapperOcc, mkDataConWorkerOcc,
-                          mkNewTyCoOcc )
+                         mkClassDataConOcc, mkSuperDictSelOcc,
+                         mkDataConWrapperOcc, mkDataConWorkerOcc,
+                         mkNewTyCoOcc, mkInstTyTcOcc, mkInstTyCoOcc ) 
 import SrcLoc          ( importedSrcLoc )
 import Maybes          ( MaybeErr(..) )
 import ErrUtils         ( Message )
@@ -62,6 +64,7 @@ import BinIface               ( readBinIface, v_IgnoreHiWay )
 import Binary          ( getBinFileWithDict )
 import Panic           ( ghcError, tryMost, showException, GhcException(..) )
 import List            ( nub )
+import Maybe            ( isJust )
 import DATA_IOREF      ( writeIORef )
 \end{code}
 
@@ -269,6 +272,10 @@ badDepMsg mod
 -- each binder with the right package info in it
 -- All subsequent lookups, including crucially lookups during typechecking
 -- the declaration itself, will find the fully-glorious Name
+--
+-- We handle ATs specially.  They are not main declarations, but also not
+-- implict things (in particular, adding them to `implicitTyThings' would mess
+-- things up in the renaming/type checking of source programs).
 -----------------------------------------------------
 
 addDeclsToPTE :: PackageTypeEnv -> [(Name,TyThing)] -> PackageTypeEnv
@@ -292,7 +299,8 @@ loadDecl ignore_prags mod (_version, decl)
   = do         {       -- Populate the name cache with final versions of all 
                -- the names associated with the decl
          main_name      <- mk_new_bndr mod Nothing (ifName decl)
-       ; implicit_names <- mapM (mk_new_bndr mod (Just main_name)) (ifaceDeclSubBndrs decl)
+       ; implicit_names <- mapM (mk_new_bndr mod (Just main_name)) 
+                                (ifaceDeclSubBndrs decl)
 
        -- Typecheck the thing, lazily
        -- NB. firstly, the laziness is there in case we never need the
@@ -304,9 +312,12 @@ loadDecl ignore_prags mod (_version, decl)
        ; let mini_env = mkOccEnv [(getOccName t, t) | t <- implicitTyThings thing]
              lookup n = case lookupOccEnv mini_env (getOccName n) of
                           Just thing -> thing
-                          Nothing    -> pprPanic "loadDecl" (ppr main_name <+> ppr n $$ ppr (stripped_decl) )
+                          Nothing    -> 
+                            pprPanic "loadDecl" (ppr main_name <+> 
+                                                 ppr n $$ ppr (stripped_decl))
 
-       ; returnM ((main_name, thing) : [(n, lookup n) | n <- implicit_names]) }
+       ; returnM $ (main_name, thing) :  [(n, lookup n) | n <- implicit_names]
+       }
                -- We build a list from the *known* names, with (lookup n) thunks
                -- as the TyThings.  That way we can extend the PTE without poking the
                -- thunks
@@ -345,12 +356,12 @@ ifaceDeclSubBndrs :: IfaceDecl -> [OccName]
 --
 -- If you change this, make sure you change HscTypes.implicitTyThings in sync
 
-ifaceDeclSubBndrs IfaceClass { ifCtxt = sc_ctxt, 
-                               ifName = cls_occ, 
-                               ifSigs = sigs }
+ifaceDeclSubBndrs (IfaceClass {ifCtxt = sc_ctxt, ifName = cls_occ, 
+                              ifSigs = sigs, ifATs = ats })
   = co_occs ++
     [tc_occ, dc_occ, dcww_occ] ++
-    [op | IfaceClassOp op _ _ <- sigs] ++
+    [op | IfaceClassOp op  _ _ <- sigs] ++
+    [ifName at | at <- ats ] ++
     [mkSuperDictSelOcc n cls_occ | n <- [1..n_ctxt]] 
   where
     n_ctxt = length sc_ctxt
@@ -359,7 +370,7 @@ ifaceDeclSubBndrs IfaceClass { ifCtxt = sc_ctxt,
     dc_occ  = mkClassDataConOcc cls_occ        
     co_occs | is_newtype = [mkNewTyCoOcc tc_occ]
            | otherwise  = []
-    dcww_occ | is_newtype = mkDataConWrapperOcc dc_occ -- Newtypes have wrapper but no worker
+    dcww_occ -- | is_newtype = mkDataConWrapperOcc dc_occ      -- Newtypes have wrapper but no worker
             | otherwise  = mkDataConWorkerOcc dc_occ   -- Otherwise worker but no wrapper
     is_newtype = n_sigs + n_ctxt == 1                  -- Sigh 
 
@@ -369,13 +380,18 @@ ifaceDeclSubBndrs IfaceData {ifCons = IfAbstractTyCon}
 ifaceDeclSubBndrs (IfaceData {ifName = tc_occ,
                              ifCons = IfNewTyCon (
                                         IfCon { ifConOcc = con_occ, 
-                                                ifConFields = fields})})
-  = fields ++ [con_occ, mkDataConWrapperOcc con_occ, mkNewTyCoOcc tc_occ]
-       -- Wrapper, no worker; see MkId.mkDataConIds
+                                                          ifConFields = fields
+                                                        }),
+                             ifFamInst = famInst}) 
+  = fields ++ [con_occ, mkDataConWorkerOcc con_occ, mkNewTyCoOcc tc_occ]
+    ++ famInstCo famInst tc_occ
 
-ifaceDeclSubBndrs (IfaceData {ifCons = IfDataTyCon cons})
+ifaceDeclSubBndrs (IfaceData {ifName = tc_occ,
+                             ifCons = IfDataTyCon cons, 
+                             ifFamInst = famInst})
   = nub (concatMap ifConFields cons)   -- Eliminate duplicate fields
     ++ concatMap dc_occs cons
+    ++ famInstCo famInst tc_occ
   where
     dc_occs con_decl
        | has_wrapper = [con_occ, work_occ, wrap_occ]
@@ -386,9 +402,16 @@ ifaceDeclSubBndrs (IfaceData {ifCons = IfDataTyCon cons})
          wrap_occ = mkDataConWrapperOcc con_occ
          work_occ = mkDataConWorkerOcc con_occ
          has_wrapper = any isMarkedStrict strs -- See MkId.mkDataConIds (sigh)
+                       || not (null . ifConEqSpec $ con_decl)
+                       || isJust famInst
                -- ToDo: may miss strictness in existential dicts
 
 ifaceDeclSubBndrs _other = []
+
+-- coercion for data/newtype family instances
+famInstCo Nothing              baseOcc = []
+famInstCo (Just (_, _, index)) baseOcc = [mkInstTyTcOcc index baseOcc,
+                                         mkInstTyCoOcc index baseOcc]
 \end{code}
 
 
@@ -578,7 +601,6 @@ pprModIface :: ModIface -> SDoc
 -- Show a ModIface
 pprModIface iface
  = vcat [ ptext SLIT("interface")
-               <+> ppr_package (mi_package iface)
                <+> ppr (mi_module iface) <+> pp_boot 
                <+> ppr (mi_mod_vers iface) <+> pp_sub_vers
                <+> (if mi_orphan iface then ptext SLIT("[orphan module]") else empty)
@@ -596,8 +618,6 @@ pprModIface iface
   where
     pp_boot | mi_boot iface = ptext SLIT("[boot]")
            | otherwise     = empty
-    ppr_package HomePackage = empty
-    ppr_package (ExtPackage id) = doubleQuotes (ppr id)
 
     exp_vers  = mi_exp_vers iface
     rule_vers = mi_rule_vers iface