+deSugar :: DynFlags
+ -> PersistentCompilerState -> HomeSymbolTable
+ -> Module -> PrintUnqualified
+ -> TcResults
+ -> IO (ModDetails, (SDoc, SDoc, [CoreBndr]))
+
+deSugar dflags pcs hst mod_name unqual
+ (TcResults {tc_env = type_env,
+ tc_binds = all_binds,
+ tc_insts = insts,
+ tc_rules = rules,
+ tc_fords = fo_decls})
+ = do { showPass dflags "Desugar"
+ ; us <- mkSplitUniqSupply 'd'
+
+ -- Do desugaring
+ ; let (ds_result, ds_warns) = initDs dflags us lookup mod_name
+ (dsProgram mod_name all_binds rules fo_decls)
+
+ (ds_binds, ds_rules, foreign_stuff) = ds_result
+
+ mod_details = ModDetails { md_types = type_env,
+ md_insts = insts,
+ md_rules = ds_rules,
+ md_binds = ds_binds }
+
+ -- Display any warnings
+ ; doIfSet (not (isEmptyBag ds_warns))
+ (printErrs unqual (pprBagOfWarnings ds_warns))
+
+ -- Lint result if necessary
+ ; endPass dflags "Desugar" Opt_D_dump_ds ds_binds
+
+ -- Dump output
+ ; doIfSet (dopt Opt_D_dump_ds dflags)
+ (printDump (ppr_ds_rules ds_rules))
+
+ ; return (mod_details, foreign_stuff)
+ }
+
+ where
+ -- The lookup function passed to initDs is used for well-known Ids,
+ -- such as fold, build, cons etc, so the chances are
+ -- it'll be found in the package symbol table. That's
+ -- why we don't merge all these tables
+ pte = pcs_PTE pcs
+ lookup n = case lookupType hst pte n of {
+ Just (AnId v) -> v ;
+ other ->
+ case lookupNameEnv type_env n of
+ Just (AnId v) -> v ;
+ other -> pprPanic "Desugar: lookup:" (ppr n)
+ }
+
+deSugarExpr :: DynFlags
+ -> PersistentCompilerState -> HomeSymbolTable
+ -> Module -> PrintUnqualified
+ -> TypecheckedHsExpr
+ -> IO CoreExpr
+deSugarExpr dflags pcs hst mod_name unqual tc_expr
+ = do { showPass dflags "Desugar"
+ ; us <- mkSplitUniqSupply 'd'
+
+ -- Do desugaring
+ ; let (core_expr, ds_warns) = initDs dflags us lookup mod_name (dsExpr tc_expr)
+
+ -- Display any warnings
+ ; doIfSet (not (isEmptyBag ds_warns))
+ (printErrs unqual (pprBagOfWarnings ds_warns))
+
+ -- Dump output
+ ; dumpIfSet_dyn dflags Opt_D_dump_ds "Desugared" (pprCoreExpr core_expr)
+
+ ; return core_expr
+ }
+ where
+ pte = pcs_PTE pcs
+ lookup n = case lookupType hst pte n of
+ Just (AnId v) -> v
+ other -> pprPanic "Desugar: lookup:" (ppr n)
+
+dsProgram mod_name all_binds rules fo_decls
+ = dsMonoBinds auto_scc all_binds [] `thenDs` \ core_prs ->
+ dsForeigns mod_name fo_decls `thenDs` \ (fe_binders, foreign_binds, h_code, c_code) ->
+ let
+ ds_binds = [Rec (foreign_binds ++ core_prs)]
+ -- Notice that we put the whole lot in a big Rec, even the foreign binds
+ -- When compiling PrelFloat, which defines data Float = F# Float#
+ -- we want F# to be in scope in the foreign marshalling code!
+ -- You might think it doesn't matter, but the simplifier brings all top-level
+ -- things into the in-scope set before simplifying; so we get no unfolding for F#!
+
+ local_binders = mkVarSet (bindersOfBinds ds_binds)
+ in
+ mapDs (dsRule local_binders) rules `thenDs` \ rules' ->
+ returnDs (ds_binds, rules', (h_code, c_code, fe_binders))
+ where
+ auto_scc | opt_SccProfilingOn = TopLevel
+ | otherwise = NoSccs
+
+ppr_ds_rules [] = empty
+ppr_ds_rules rules
+ = text "" $$ text "-------------- DESUGARED RULES -----------------" $$
+ vcat (map pprIdCoreRule rules)
+\end{code}