\section[Desugar]{@deSugar@: the main function}
\begin{code}
-module Desugar ( deSugar ) where
+module Desugar ( deSugar, deSugarExpr,
+ deSugarCore ) where
#include "HsVersions.h"
import CmdLineOpts ( DynFlags, DynFlag(..), dopt, opt_SccProfilingOn )
+import HscTypes ( ModDetails(..), TypeEnv )
import HsSyn ( MonoBinds, RuleDecl(..), RuleBndr(..),
HsExpr(..), HsBinds(..), MonoBinds(..) )
-import TcHsSyn ( TypecheckedRuleDecl )
+import TcHsSyn ( TypecheckedRuleDecl, TypecheckedHsExpr,
+ TypecheckedCoreBind )
import TcModule ( TcResults(..) )
import Id ( Id )
import CoreSyn
-import PprCore ( pprIdCoreRule )
+import PprCore ( pprIdRules, pprCoreExpr )
import Subst ( substExpr, mkSubst, mkInScopeSet )
import DsMonad
import DsExpr ( dsExpr )
import DsExpr () -- Forces DsExpr to be compiled; DsBinds only
-- depends on DsExpr.hi-boot.
import Module ( Module )
+import Id ( Id )
+import NameEnv ( lookupNameEnv )
import VarEnv
import VarSet
import Bag ( isEmptyBag )
-import CoreLint ( beginPass, endPass )
-import ErrUtils ( doIfSet, pprBagOfWarnings )
+import CoreLint ( showPass, endPass )
+import ErrUtils ( doIfSet, dumpIfSet_dyn, pprBagOfWarnings )
import Outputable
-import UniqSupply ( UniqSupply )
-import HscTypes ( HomeSymbolTable )
+import UniqSupply ( mkSplitUniqSupply )
+import HscTypes ( HomeSymbolTable, PersistentCompilerState(..), TyThing(..), lookupType, )
\end{code}
%************************************************************************
\begin{code}
deSugar :: DynFlags
- -> Module
- -> UniqSupply
- -> HomeSymbolTable
+ -> PersistentCompilerState -> HomeSymbolTable
+ -> Module -> PrintUnqualified
-> TcResults
- -> IO ([CoreBind], [(Id,CoreRule)], SDoc, SDoc, [CoreBndr])
-
-deSugar dflags mod_name us hst
- (TcResults {tc_env = global_val_env,
- tc_pcs = pcs,
- tc_binds = all_binds,
- tc_rules = rules,
- tc_fords = fo_decls})
- = do
- beginPass dflags "Desugar"
+ -> IO (ModDetails, (SDoc, SDoc, [FAST_STRING], [CoreBndr]))
+
+deSugar dflags pcs hst mod_name unqual
+ (TcResults {tc_env = type_env,
+ tc_binds = all_binds,
+ tc_insts = insts,
+ tc_rules = rules,
+-- tc_cbinds = core_binds,
+ tc_fords = fo_decls})
+ = do { showPass dflags "Desugar"
+ ; us <- mkSplitUniqSupply 'd'
+
-- Do desugaring
- let (result, ds_warns) =
- initDs dflags us (hst,pcs,global_val_env) mod_name
- (dsProgram mod_name all_binds rules fo_decls)
- (ds_binds, ds_rules, _, _, _) = result
+ ; 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
+
+{-
+ addCoreBinds ls =
+ case core_binds of
+ [] -> ls
+ cs -> (Rec cs) : ls
+-}
+ 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'
- -- Display any warnings
- doIfSet (not (isEmptyBag ds_warns))
- (printErrs (pprBagOfWarnings ds_warns))
+ -- Do desugaring
+ ; let (core_expr, ds_warns) = initDs dflags us lookup mod_name (dsExpr tc_expr)
- -- Lint result if necessary
- let do_dump_ds = dopt Opt_D_dump_ds dflags
- endPass dflags "Desugar" do_dump_ds ds_binds
+ -- Display any warnings
+ ; doIfSet (not (isEmptyBag ds_warns))
+ (printErrs unqual (pprBagOfWarnings ds_warns))
- doIfSet do_dump_ds (printDump (ppr_ds_rules ds_rules))
+ -- Dump output
+ ; dumpIfSet_dyn dflags Opt_D_dump_ds "Desugared" (pprCoreExpr core_expr)
- return result
+ ; 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) ->
+ dsForeigns mod_name fo_decls `thenDs` \ (fe_binders, foreign_binds, h_code, c_code, headers) ->
let
ds_binds = [Rec (foreign_binds ++ core_prs)]
-- Notice that we put the whole lot in a big Rec, even the foreign binds
local_binders = mkVarSet (bindersOfBinds ds_binds)
in
mapDs (dsRule local_binders) rules `thenDs` \ rules' ->
- returnDs (ds_binds, rules', h_code, c_code, fe_binders)
+ returnDs (ds_binds, rules', (h_code, c_code, headers, 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)
+ pprIdRules rules
+\end{code}
+
+Simplest thing in the world, desugaring External Core:
+
+\begin{code}
+deSugarCore :: TypeEnv -> [TypecheckedCoreBind]
+ -> IO (ModDetails, (SDoc, SDoc, [FAST_STRING], [CoreBndr]))
+deSugarCore type_env cs = do
+ let
+ mod_details
+ = ModDetails { md_types = type_env
+ , md_insts = []
+ , md_rules = []
+ , md_binds = [Rec (map (\ (lhs,_,rhs) -> (lhs,rhs)) cs)]
+ }
+
+ no_foreign_stuff = (empty,empty,[],[])
+ return (mod_details, no_foreign_stuff)
+
\end{code}
\begin{code}
dsRule :: IdSet -> TypecheckedRuleDecl -> DsM (Id, CoreRule)
-dsRule in_scope (HsRule name sig_tvs vars lhs rhs loc)
+dsRule in_scope (IfaceRuleOut fun rule) -- Built-in rules come this way
+ = returnDs (fun, rule)
+
+dsRule in_scope (HsRule name act vars lhs rhs loc)
= putSrcLocDs loc $
ds_lhs all_vars lhs `thenDs` \ (fn, args) ->
dsExpr rhs `thenDs` \ core_rhs ->
- returnDs (fn, Rule name tpl_vars args core_rhs)
+ returnDs (fn, Rule name act tpl_vars args core_rhs)
where
- tpl_vars = sig_tvs ++ [var | RuleBndr var <- vars]
+ tpl_vars = [var | RuleBndr var <- vars]
all_vars = mkInScopeSet (in_scope `unionVarSet` mkVarSet tpl_vars)
ds_lhs all_vars lhs