Rough matches for family instances

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

diff --git a/compiler/typecheck/TcInstDcls.lhs b/compiler/typecheck/TcInstDcls.lhs
index 3236b67..0b4f8b0 100644 (file)
--- a/compiler/typecheck/TcInstDcls.lhs
+++ b/compiler/typecheck/TcInstDcls.lhs
@@ -24,7 +24,7 @@ import Inst           ( newDictBndr, newDictBndrs, instToId, showLIE,
                          getOverlapFlag, tcExtendLocalInstEnv )
 import InstEnv         ( mkLocalInstance, instanceDFunId )
 import FamInst         ( tcExtendLocalFamInstEnv )
-import FamInstEnv      ( extractFamInsts )
+import FamInstEnv      ( mkLocalFamInst )
 import TcDeriv         ( tcDeriving )
 import TcEnv           ( InstInfo(..), InstBindings(..), 
                          newDFunName, tcExtendIdEnv, tcExtendGlobalEnv
@@ -179,16 +179,19 @@ tcInstDecls1 tycl_decls inst_decls deriv_decls
                -- (3) Instances from generic class declarations
        ; generic_inst_info <- getGenericInstances clas_decls
 
-       -- (3) Compute instances from "deriving" clauses; 
-       -- This stuff computes a context for the derived instance decl, so it
-       -- needs to know about all the instances possible; hence inst_env4
-    tcDeriving tycl_decls      `thenM` \ (deriv_inst_info, deriv_binds) ->
-    addInsts deriv_inst_info   $
+               -- Next, construct the instance environment so far, consisting
+               -- of 
+               --   a) local instance decls
+               --   b) generic instances
+               --   c) local family instance decls
+       ; addInsts local_info         $ do {
+       ; addInsts generic_inst_info  $ do {
+       ; addFamInsts at_idx_tycon    $ do {
 
                -- (4) Compute instances from "deriving" clauses; 
                -- This stuff computes a context for the derived instance
                -- decl, so it needs to know about all the instances possible
-       ; (deriv_inst_info, deriv_binds) <- tcDeriving tycl_decls
+       ; (deriv_inst_info, deriv_binds) <- tcDeriving tycl_decls deriv_decls
        ; addInsts deriv_inst_info   $ do {
 
        ; gbl_env <- getGblEnv
@@ -224,7 +227,11 @@ addInsts infos thing_inside
 
 addFamInsts :: [TyThing] -> TcM a -> TcM a
 addFamInsts tycons thing_inside
-  = tcExtendLocalFamInstEnv (extractFamInsts tycons) thing_inside
+  = tcExtendLocalFamInstEnv (map mkLocalFamInstTyThing tycons) thing_inside
+  where
+    mkLocalFamInstTyThing (ATyCon tycon) = mkLocalFamInst tycon
+    mkLocalFamInstTyThing tything       = pprPanic "TcInstDcls.addFamInsts"
+                                                   (ppr tything)
 \end{code} 
 
 \begin{code}