+ -> TcM (PackageInstEnv, InstEnv, [InstInfo], RenamedHsBinds)
+
+tcInstDecls1 inst_env0 prs hst unf_env get_fixity this_mod decls
+ = let
+ inst_decls = [inst_decl | InstD inst_decl <- decls]
+ tycl_decls = [decl | TyClD decl <- decls]
+ clas_decls = filter isClassDecl tycl_decls
+ (iface_inst_ds, local_inst_ds) = partition isIfaceInstDecl inst_decls
+ in
+ -- (1) Do the ordinary instance declarations
+ mapNF_Tc tcLocalInstDecl1 local_inst_ds `thenNF_Tc` \ local_inst_infos ->
+ mapNF_Tc tcImportedInstDecl1 iface_inst_ds `thenNF_Tc` \ iface_dfuns ->
+
+ -- (2) Instances from generic class declarations
+ getGenericInstances clas_decls `thenTc` \ generic_inst_info ->
+
+ -- Next, construct the instance environment so far, consisting of
+ -- a) cached non-home-package InstEnv (gotten from pcs) inst_env0
+ -- b) imported instance decls (not in the home package) inst_env1
+ -- c) imported instance decls (from this module) inst_env2
+ -- c) other modules in this package (gotten from hst) inst_env3
+ -- d) local instance decls inst_env4
+ -- e) generic instances inst_env5
+ -- The result of (b) replaces the cached InstEnv in the PCS
+ --
+ -- Note that iface_dfuns may contain not only insts that we demand-loaded
+ -- from package interface files, but also instances from the current module
+ -- in the case where we are loading this module's interface file in GHCi,
+ -- so we partition the iface_dfuns into package instances and local instances
+ -- below so that we don't end up with home package instances in the PCS.
+ --
+ -- There can't be any instance declarations from the home
+ -- package other than from the current module (with the
+ -- compilation manager) because they are loaded explicitly by
+ -- the compilation manager. The partition is really only
+ -- necessary when we're under control of the compilation
+ -- manager.
+ let
+ local_inst_info = catMaybes local_inst_infos
+ (local_iface_dfuns, pkg_iface_dfuns) = partition isHomePackageThing iface_dfuns
+ hst_dfuns = foldModuleEnv ((++) . md_insts) [] hst
+ in
+
+-- pprTrace "tcInstDecls" (vcat [ppr imported_dfuns, ppr hst_dfuns]) $
+
+ addInstDFuns inst_env0 pkg_iface_dfuns `thenNF_Tc` \ inst_env1 ->
+ addInstDFuns inst_env1 hst_dfuns `thenNF_Tc` \ inst_env2 ->
+ addInstDFuns inst_env2 local_iface_dfuns `thenNF_Tc` \ inst_env3 ->
+ addInstInfos inst_env3 local_inst_info `thenNF_Tc` \ inst_env4 ->
+ addInstInfos inst_env4 generic_inst_info `thenNF_Tc` \ inst_env5 ->
+
+ -- (3) Compute instances from "deriving" clauses;
+ -- note that we only do derivings for things in this module;
+ -- we ignore deriving decls from interfaces!
+ -- This stuff computes a context for the derived instance decl, so it
+ -- needs to know about all the instances possible; hence inst_env4
+ tcDeriving prs this_mod inst_env4 get_fixity tycl_decls
+ `thenTc` \ (deriv_inst_info, deriv_binds) ->
+ addInstInfos inst_env4 deriv_inst_info `thenNF_Tc` \ final_inst_env ->
+
+ returnTc (inst_env1,
+ final_inst_env,
+ generic_inst_info ++ deriv_inst_info ++ local_inst_info,
+ deriv_binds)
+
+addInstInfos :: InstEnv -> [InstInfo] -> NF_TcM InstEnv
+addInstInfos inst_env infos = addInstDFuns inst_env (map iDFunId infos)
+
+addInstDFuns :: InstEnv -> [DFunId] -> NF_TcM InstEnv
+addInstDFuns inst_env dfuns
+ = getDOptsTc `thenNF_Tc` \ dflags ->