\begin{code}
module RnExpr (
- rnMatch, rnGRHSs, rnPat, rnExpr, rnExprs,
- checkPrecMatch
+ rnMatchGroup, rnMatch, rnGRHSs, rnLExpr, rnExpr, rnStmts,
+ checkPrecMatch, checkTH
) where
#include "HsVersions.h"
-import {-# SOURCE #-} RnBinds ( rnBinds )
-import {-# SOURCE #-} RnSource ( rnHsSigType, rnHsPolyType, rnHsType )
+import {-# SOURCE #-} RnSource ( rnSrcDecls, rnBindGroupsAndThen, rnBindGroups, rnSplice )
+
+-- RnSource imports RnBinds.rnTopMonoBinds, RnExpr.rnExpr
+-- RnBinds imports RnExpr.rnMatch, etc
+-- RnExpr imports [boot] RnSource.rnSrcDecls, RnSource.rnBinds
import HsSyn
-import RdrHsSyn
import RnHsSyn
-import RnMonad
+import TcRnMonad
import RnEnv
-import RnIfaces ( lookupFixity )
-import CmdLineOpts ( opt_GlasgowExts, opt_IgnoreAsserts )
-import BasicTypes ( Fixity(..), FixityDirection(..), defaultFixity, negateFixity, negatePrecedence )
-import PrelInfo ( numClass_RDR, fractionalClass_RDR, eqClass_RDR,
- ccallableClass_RDR, creturnableClass_RDR,
- monadClass_RDR, enumClass_RDR, ordClass_RDR,
- ratioDataCon_RDR, negate_RDR, assertErr_RDR,
- ioDataCon_RDR
- )
-import TysPrim ( charPrimTyCon, addrPrimTyCon, intPrimTyCon,
- floatPrimTyCon, doublePrimTyCon
- )
-import Name ( nameUnique, isLocallyDefined, NamedThing(..)
- , mkSysLocalName, nameSrcLoc
- )
+import OccName ( plusOccEnv )
+import RnNames ( importsFromLocalDecls )
+import RnTypes ( rnHsTypeFVs, rnLPat, rnOverLit, rnPatsAndThen, rnLit,
+ dupFieldErr, precParseErr, sectionPrecErr, patSigErr,
+ checkTupSize )
+import CmdLineOpts ( DynFlag(..) )
+import BasicTypes ( Fixity(..), FixityDirection(..), negateFixity, compareFixity )
+import PrelNames ( hasKey, assertIdKey, assertErrorName,
+ loopAName, choiceAName, appAName, arrAName, composeAName, firstAName,
+ negateName, monadNames, mfixName )
+import Name ( Name, nameOccName )
import NameSet
+import RdrName ( RdrName )
+import UnicodeUtil ( stringToUtf8 )
import UniqFM ( isNullUFM )
-import FiniteMap ( elemFM )
-import UniqSet ( emptyUniqSet, UniqSet )
-import Unique ( assertIdKey )
-import Util ( removeDups )
-import ListSetOps ( unionLists )
-import Maybes ( maybeToBool )
+import UniqSet ( emptyUniqSet )
+import Util ( isSingleton )
+import ListSetOps ( removeDups )
import Outputable
-\end{code}
-
-
-*********************************************************
-* *
-\subsection{Patterns}
-* *
-*********************************************************
-
-\begin{code}
-rnPat :: RdrNamePat -> RnMS (RenamedPat, FreeVars)
-
-rnPat WildPatIn = returnRn (WildPatIn, emptyFVs)
-
-rnPat (VarPatIn name)
- = lookupBndrRn name `thenRn` \ vname ->
- returnRn (VarPatIn vname, emptyFVs)
+import SrcLoc ( Located(..), unLoc, getLoc, combineLocs, cmpLocated )
+import FastString
-rnPat (SigPatIn pat ty)
- | opt_GlasgowExts
- = rnPat pat `thenRn` \ (pat', fvs1) ->
- rnHsPolyType doc ty `thenRn` \ (ty', fvs2) ->
- returnRn (SigPatIn pat' ty', fvs1 `plusFV` fvs2)
-
- | otherwise
- = addErrRn (patSigErr ty) `thenRn_`
- rnPat pat
- where
- doc = text "a pattern type-signature"
-
-rnPat (LitPatIn lit)
- = litOccurrence lit `thenRn` \ fvs1 ->
- lookupImplicitOccRn eqClass_RDR `thenRn` \ eq -> -- Needed to find equality on pattern
- returnRn (LitPatIn lit, fvs1 `addOneFV` eq)
-
-rnPat (LazyPatIn pat)
- = rnPat pat `thenRn` \ (pat', fvs) ->
- returnRn (LazyPatIn pat', fvs)
-
-rnPat (AsPatIn name pat)
- = rnPat pat `thenRn` \ (pat', fvs) ->
- lookupBndrRn name `thenRn` \ vname ->
- returnRn (AsPatIn vname pat', fvs)
-
-rnPat (ConPatIn con pats)
- = lookupOccRn con `thenRn` \ con' ->
- mapFvRn rnPat pats `thenRn` \ (patslist, fvs) ->
- returnRn (ConPatIn con' patslist, fvs `addOneFV` con')
-
-rnPat (ConOpPatIn pat1 con _ pat2)
- = rnPat pat1 `thenRn` \ (pat1', fvs1) ->
- lookupOccRn con `thenRn` \ con' ->
- rnPat pat2 `thenRn` \ (pat2', fvs2) ->
-
- getModeRn `thenRn` \ mode ->
- -- See comments with rnExpr (OpApp ...)
- (case mode of
- InterfaceMode -> returnRn (ConOpPatIn pat1' con' defaultFixity pat2')
- SourceMode -> lookupFixity con' `thenRn` \ fixity ->
- mkConOpPatRn pat1' con' fixity pat2'
- ) `thenRn` \ pat' ->
- returnRn (pat', fvs1 `plusFV` fvs2 `addOneFV` con')
-
--- Negated patters can only be literals, and they are dealt with
--- by negating the literal at compile time, not by using the negation
--- operation in Num. So we don't need to make an implicit reference
--- to negate_RDR.
-rnPat neg@(NegPatIn pat)
- = checkRn (valid_neg_pat pat) (negPatErr neg)
- `thenRn_`
- rnPat pat `thenRn` \ (pat', fvs) ->
- returnRn (NegPatIn pat', fvs)
- where
- valid_neg_pat (LitPatIn (HsInt _)) = True
- valid_neg_pat (LitPatIn (HsIntPrim _)) = True
- valid_neg_pat (LitPatIn (HsFrac _)) = True
- valid_neg_pat (LitPatIn (HsFloatPrim _)) = True
- valid_neg_pat (LitPatIn (HsDoublePrim _)) = True
- valid_neg_pat _ = False
-
-rnPat (ParPatIn pat)
- = rnPat pat `thenRn` \ (pat', fvs) ->
- returnRn (ParPatIn pat', fvs)
-
-rnPat (NPlusKPatIn name lit)
- = litOccurrence lit `thenRn` \ fvs ->
- lookupImplicitOccRn ordClass_RDR `thenRn` \ ord ->
- lookupBndrRn name `thenRn` \ name' ->
- returnRn (NPlusKPatIn name' lit, fvs `addOneFV` ord)
-
-rnPat (ListPatIn pats)
- = mapFvRn rnPat pats `thenRn` \ (patslist, fvs) ->
- returnRn (ListPatIn patslist, fvs `addOneFV` listTyCon_name)
-
-rnPat (TuplePatIn pats boxed)
- = mapFvRn rnPat pats `thenRn` \ (patslist, fvs) ->
- returnRn (TuplePatIn patslist boxed, fvs `addOneFV` tycon_name)
- where
- tycon_name = tupleTyCon_name boxed (length pats)
-
-rnPat (RecPatIn con rpats)
- = lookupOccRn con `thenRn` \ con' ->
- rnRpats rpats `thenRn` \ (rpats', fvs) ->
- returnRn (RecPatIn con' rpats', fvs `addOneFV` con')
+import List ( unzip4 )
\end{code}
+
************************************************************************
* *
\subsection{Match}
************************************************************************
\begin{code}
-rnMatch :: RdrNameMatch -> RnMS (RenamedMatch, FreeVars)
+rnMatchGroup :: HsMatchContext Name -> MatchGroup RdrName -> RnM (MatchGroup Name, FreeVars)
+rnMatchGroup ctxt (MatchGroup ms _)
+ = mapFvRn (rnMatch ctxt) ms `thenM` \ (new_ms, ms_fvs) ->
+ returnM (MatchGroup new_ms placeHolderType, ms_fvs)
-rnMatch match@(Match _ pats maybe_rhs_sig grhss)
- = pushSrcLocRn (getMatchLoc match) $
+rnMatch :: HsMatchContext Name -> LMatch RdrName -> RnM (LMatch Name, FreeVars)
+rnMatch ctxt = wrapLocFstM (rnMatch' ctxt)
- -- Find the universally quantified type variables
- -- in the pattern type signatures
- getLocalNameEnv `thenRn` \ name_env ->
- let
- tyvars_in_sigs = rhs_sig_tyvars `unionLists` tyvars_in_pats
- rhs_sig_tyvars = case maybe_rhs_sig of
- Nothing -> []
- Just ty -> extractHsTyRdrNames ty
- tyvars_in_pats = extractPatsTyVars pats
- forall_tyvars = filter (not . (`elemFM` name_env)) tyvars_in_sigs
- doc = text "a pattern type-signature"
- in
- bindTyVarsFVRn doc (map UserTyVar forall_tyvars) $ \ sig_tyvars ->
-
- -- Note that we do a single bindLocalsRn for all the
- -- matches together, so that we spot the repeated variable in
- -- f x x = 1
- bindLocalsFVRn doc (collectPatsBinders pats) $ \ new_binders ->
-
- mapFvRn rnPat pats `thenRn` \ (pats', pat_fvs) ->
- rnGRHSs grhss `thenRn` \ (grhss', grhss_fvs) ->
+rnMatch' ctxt match@(Match pats maybe_rhs_sig grhss)
+ =
+ -- Deal with the rhs type signature
+ bindPatSigTyVarsFV rhs_sig_tys $
+ doptM Opt_GlasgowExts `thenM` \ opt_GlasgowExts ->
(case maybe_rhs_sig of
- Nothing -> returnRn (Nothing, emptyFVs)
- Just ty | opt_GlasgowExts -> rnHsType doc ty `thenRn` \ (ty', ty_fvs) ->
- returnRn (Just ty', ty_fvs)
- | otherwise -> addErrRn (patSigErr ty) `thenRn_`
- returnRn (Nothing, emptyFVs)
- ) `thenRn` \ (maybe_rhs_sig', ty_fvs) ->
-
- let
- binder_set = mkNameSet new_binders
- unused_binders = nameSetToList (binder_set `minusNameSet` grhss_fvs)
- all_fvs = grhss_fvs `plusFV` pat_fvs `plusFV` ty_fvs
- in
- warnUnusedMatches unused_binders `thenRn_`
-
- returnRn (Match sig_tyvars pats' maybe_rhs_sig' grhss', all_fvs)
- -- The bindLocals and bindTyVars will remove the bound FVs
+ Nothing -> returnM (Nothing, emptyFVs)
+ Just ty | opt_GlasgowExts -> rnHsTypeFVs doc_sig ty `thenM` \ (ty', ty_fvs) ->
+ returnM (Just ty', ty_fvs)
+ | otherwise -> addLocErr ty patSigErr `thenM_`
+ returnM (Nothing, emptyFVs)
+ ) `thenM` \ (maybe_rhs_sig', ty_fvs) ->
+
+ -- Now the main event
+ rnPatsAndThen ctxt True pats $ \ pats' ->
+ rnGRHSs ctxt grhss `thenM` \ (grhss', grhss_fvs) ->
+
+ returnM (Match pats' maybe_rhs_sig' grhss', grhss_fvs `plusFV` ty_fvs)
+ -- The bindPatSigTyVarsFV and rnPatsAndThen will remove the bound FVs
+ where
+ rhs_sig_tys = case maybe_rhs_sig of
+ Nothing -> []
+ Just ty -> [ty]
+ doc_sig = text "In a result type-signature"
\end{code}
+
%************************************************************************
%* *
\subsubsection{Guarded right-hand sides (GRHSs)}
%************************************************************************
\begin{code}
-rnGRHSs :: RdrNameGRHSs -> RnMS (RenamedGRHSs, FreeVars)
-
-rnGRHSs (GRHSs grhss binds maybe_ty)
- = ASSERT( not (maybeToBool maybe_ty) )
- rnBinds binds $ \ binds' ->
- mapFvRn rnGRHS grhss `thenRn` \ (grhss', fvGRHSs) ->
- returnRn (GRHSs grhss' binds' Nothing, fvGRHSs)
-
-rnGRHS (GRHS guarded locn)
- = pushSrcLocRn locn $
- (if not (opt_GlasgowExts || is_standard_guard guarded) then
- addWarnRn (nonStdGuardErr guarded)
- else
- returnRn ()
- ) `thenRn_`
-
- rnStmts rnExpr guarded `thenRn` \ (guarded', fvs) ->
- returnRn (GRHS guarded' locn, fvs)
+rnGRHSs :: HsMatchContext Name -> GRHSs RdrName -> RnM (GRHSs Name, FreeVars)
+
+-- gaw 2004
+rnGRHSs ctxt (GRHSs grhss binds)
+ = rnBindGroupsAndThen binds $ \ binds' ->
+ mapFvRn (rnGRHS ctxt) grhss `thenM` \ (grhss', fvGRHSs) ->
+ returnM (GRHSs grhss' binds', fvGRHSs)
+
+rnGRHS :: HsMatchContext Name -> LGRHS RdrName -> RnM (LGRHS Name, FreeVars)
+rnGRHS ctxt = wrapLocFstM (rnGRHS' ctxt)
+
+rnGRHS' ctxt (GRHS guarded)
+ = doptM Opt_GlasgowExts `thenM` \ opt_GlasgowExts ->
+ checkM (opt_GlasgowExts || is_standard_guard guarded)
+ (addWarn (nonStdGuardErr guarded)) `thenM_`
+
+ rnStmts (PatGuard ctxt) guarded `thenM` \ (guarded', fvs) ->
+ returnM (GRHS guarded', fvs)
where
-- Standard Haskell 1.4 guards are just a single boolean
-- expression, rather than a list of qualifiers as in the
-- Glasgow extension
- is_standard_guard [ExprStmt _ _] = True
- is_standard_guard [GuardStmt _ _, ExprStmt _ _] = True
- is_standard_guard other = False
+ is_standard_guard [L _ (ResultStmt _)] = True
+ is_standard_guard [L _ (ExprStmt _ _), L _ (ResultStmt _)] = True
+ is_standard_guard other = False
\end{code}
%************************************************************************
%************************************************************************
\begin{code}
-rnExprs :: [RdrNameHsExpr] -> RnMS ([RenamedHsExpr], FreeVars)
+rnExprs :: [LHsExpr RdrName] -> RnM ([LHsExpr Name], FreeVars)
rnExprs ls = rnExprs' ls emptyUniqSet
where
- rnExprs' [] acc = returnRn ([], acc)
+ rnExprs' [] acc = returnM ([], acc)
rnExprs' (expr:exprs) acc
- = rnExpr expr `thenRn` \ (expr', fvExpr) ->
+ = rnLExpr expr `thenM` \ (expr', fvExpr) ->
-- Now we do a "seq" on the free vars because typically it's small
-- or empty, especially in very long lists of constants
let
acc' = acc `plusFV` fvExpr
in
- (grubby_seqNameSet acc' rnExprs') exprs acc' `thenRn` \ (exprs', fvExprs) ->
- returnRn (expr':exprs', fvExprs)
+ (grubby_seqNameSet acc' rnExprs') exprs acc' `thenM` \ (exprs', fvExprs) ->
+ returnM (expr':exprs', fvExprs)
-- Grubby little function to do "seq" on namesets; replace by proper seq when GHC can do seq
grubby_seqNameSet ns result | isNullUFM ns = result
Variables. We look up the variable and return the resulting name.
\begin{code}
-rnExpr :: RdrNameHsExpr -> RnMS (RenamedHsExpr, FreeVars)
+rnLExpr :: LHsExpr RdrName -> RnM (LHsExpr Name, FreeVars)
+rnLExpr = wrapLocFstM rnExpr
+
+rnExpr :: HsExpr RdrName -> RnM (HsExpr Name, FreeVars)
rnExpr (HsVar v)
- = lookupOccRn v `thenRn` \ name ->
- if nameUnique name == assertIdKey then
- -- We expand it to (GHCerr.assert__ location)
- mkAssertExpr
+ = lookupOccRn v `thenM` \ name ->
+ doptM Opt_IgnoreAsserts `thenM` \ ignore_asserts ->
+ if name `hasKey` assertIdKey && not ignore_asserts then
+ -- We expand it to (GHC.Err.assertError location_string)
+ mkAssertErrorExpr `thenM` \ (e, fvs) ->
+ returnM (e, fvs `addOneFV` name)
+ -- Keep 'assert' as a free var, to ensure it's not reported as unused!
else
- -- The normal case
- returnRn (HsVar name, unitFV name)
+ -- The normal case. Even if the Id was 'assert', if we are
+ -- ignoring assertions we leave it as GHC.Base.assert;
+ -- this function just ignores its first arg.
+ returnM (HsVar name, unitFV name)
+
+rnExpr (HsIPVar v)
+ = newIPNameRn v `thenM` \ name ->
+ returnM (HsIPVar name, emptyFVs)
rnExpr (HsLit lit)
- = litOccurrence lit `thenRn` \ fvs ->
- returnRn (HsLit lit, fvs)
+ = rnLit lit `thenM_`
+ returnM (HsLit lit, emptyFVs)
-rnExpr (HsLam match)
- = rnMatch match `thenRn` \ (match', fvMatch) ->
- returnRn (HsLam match', fvMatch)
+rnExpr (HsOverLit lit)
+ = rnOverLit lit `thenM` \ (lit', fvs) ->
+ returnM (HsOverLit lit', fvs)
rnExpr (HsApp fun arg)
- = rnExpr fun `thenRn` \ (fun',fvFun) ->
- rnExpr arg `thenRn` \ (arg',fvArg) ->
- returnRn (HsApp fun' arg', fvFun `plusFV` fvArg)
+ = rnLExpr fun `thenM` \ (fun',fvFun) ->
+ rnLExpr arg `thenM` \ (arg',fvArg) ->
+ returnM (HsApp fun' arg', fvFun `plusFV` fvArg)
rnExpr (OpApp e1 op _ e2)
- = rnExpr e1 `thenRn` \ (e1', fv_e1) ->
- rnExpr e2 `thenRn` \ (e2', fv_e2) ->
- rnExpr op `thenRn` \ (op'@(HsVar op_name), fv_op) ->
+ = rnLExpr e1 `thenM` \ (e1', fv_e1) ->
+ rnLExpr e2 `thenM` \ (e2', fv_e2) ->
+ rnLExpr op `thenM` \ (op'@(L _ (HsVar op_name)), fv_op) ->
-- Deal with fixity
-- When renaming code synthesised from "deriving" declarations
- -- we're in Interface mode, and we should ignore fixity; assume
- -- that the deriving code generator got the association correct
- -- Don't even look up the fixity when in interface mode
- getModeRn `thenRn` \ mode ->
- (case mode of
- SourceMode -> lookupFixity op_name `thenRn` \ fixity ->
- mkOpAppRn e1' op' fixity e2'
- InterfaceMode -> returnRn (OpApp e1' op' defaultFixity e2')
- ) `thenRn` \ final_e ->
-
- returnRn (final_e,
- fv_e1 `plusFV` fv_op `plusFV` fv_e2)
+ -- we used to avoid fixity stuff, but we can't easily tell any
+ -- more, so I've removed the test. Adding HsPars in TcGenDeriv
+ -- should prevent bad things happening.
+ lookupFixityRn op_name `thenM` \ fixity ->
+ mkOpAppRn e1' op' fixity e2' `thenM` \ final_e ->
--- constant-fold some negate applications on unboxed literals. Since
--- negate is a polymorphic function, we have to do these here.
-rnExpr (NegApp (HsLit (HsIntPrim i)) _) = rnExpr (HsLit (HsIntPrim (-i)))
-rnExpr (NegApp (HsLit (HsFloatPrim i)) _) = rnExpr (HsLit (HsFloatPrim (-i)))
-rnExpr (NegApp (HsLit (HsDoublePrim i)) _) = rnExpr (HsLit (HsDoublePrim (-i)))
+ returnM (final_e,
+ fv_e1 `plusFV` fv_op `plusFV` fv_e2)
-rnExpr (NegApp e n)
- = rnExpr e `thenRn` \ (e', fv_e) ->
- lookupImplicitOccRn negate_RDR `thenRn` \ neg ->
- mkNegAppRn e' (HsVar neg) `thenRn` \ final_e ->
- returnRn (final_e, fv_e `addOneFV` neg)
+rnExpr (NegApp e _)
+ = rnLExpr e `thenM` \ (e', fv_e) ->
+ lookupSyntaxName negateName `thenM` \ (neg_name, fv_neg) ->
+ mkNegAppRn e' neg_name `thenM` \ final_e ->
+ returnM (final_e, fv_e `plusFV` fv_neg)
rnExpr (HsPar e)
- = rnExpr e `thenRn` \ (e', fvs_e) ->
- returnRn (HsPar e', fvs_e)
+ = rnLExpr e `thenM` \ (e', fvs_e) ->
+ returnM (HsPar e', fvs_e)
+
+-- Template Haskell extensions
+-- Don't ifdef-GHCI them because we want to fail gracefully
+-- (not with an rnExpr crash) in a stage-1 compiler.
+rnExpr e@(HsBracket br_body)
+ = checkTH e "bracket" `thenM_`
+ rnBracket br_body `thenM` \ (body', fvs_e) ->
+ returnM (HsBracket body', fvs_e)
+
+rnExpr e@(HsSpliceE splice)
+ = rnSplice splice `thenM` \ (splice', fvs) ->
+ returnM (HsSpliceE splice', fvs)
rnExpr section@(SectionL expr op)
- = rnExpr expr `thenRn` \ (expr', fvs_expr) ->
- rnExpr op `thenRn` \ (op', fvs_op) ->
- checkSectionPrec "left" section op' expr' `thenRn_`
- returnRn (SectionL expr' op', fvs_op `plusFV` fvs_expr)
+ = rnLExpr expr `thenM` \ (expr', fvs_expr) ->
+ rnLExpr op `thenM` \ (op', fvs_op) ->
+ checkSectionPrec InfixL section op' expr' `thenM_`
+ returnM (SectionL expr' op', fvs_op `plusFV` fvs_expr)
rnExpr section@(SectionR op expr)
- = rnExpr op `thenRn` \ (op', fvs_op) ->
- rnExpr expr `thenRn` \ (expr', fvs_expr) ->
- checkSectionPrec "right" section op' expr' `thenRn_`
- returnRn (SectionR op' expr', fvs_op `plusFV` fvs_expr)
-
-rnExpr (CCall fun args may_gc is_casm fake_result_ty)
- -- Check out the comment on RnIfaces.getNonWiredDataDecl about ccalls
- = lookupImplicitOccRn ccallableClass_RDR `thenRn` \ cc ->
- lookupImplicitOccRn creturnableClass_RDR `thenRn` \ cr ->
- lookupImplicitOccRn ioDataCon_RDR `thenRn` \ io ->
- rnExprs args `thenRn` \ (args', fvs_args) ->
- returnRn (CCall fun args' may_gc is_casm fake_result_ty,
- fvs_args `addOneFV` cc `addOneFV` cr `addOneFV` io)
+ = rnLExpr op `thenM` \ (op', fvs_op) ->
+ rnLExpr expr `thenM` \ (expr', fvs_expr) ->
+ checkSectionPrec InfixR section op' expr' `thenM_`
+ returnM (SectionR op' expr', fvs_op `plusFV` fvs_expr)
+
+rnExpr (HsCoreAnn ann expr)
+ = rnLExpr expr `thenM` \ (expr', fvs_expr) ->
+ returnM (HsCoreAnn ann expr', fvs_expr)
rnExpr (HsSCC lbl expr)
- = rnExpr expr `thenRn` \ (expr', fvs_expr) ->
- returnRn (HsSCC lbl expr', fvs_expr)
+ = rnLExpr expr `thenM` \ (expr', fvs_expr) ->
+ returnM (HsSCC lbl expr', fvs_expr)
-rnExpr (HsCase expr ms src_loc)
- = pushSrcLocRn src_loc $
- rnExpr expr `thenRn` \ (new_expr, e_fvs) ->
- mapFvRn rnMatch ms `thenRn` \ (new_ms, ms_fvs) ->
- returnRn (HsCase new_expr new_ms src_loc, e_fvs `plusFV` ms_fvs)
+rnExpr (HsLam matches)
+ = rnMatchGroup LambdaExpr matches `thenM` \ (matches', fvMatch) ->
+ returnM (HsLam matches', fvMatch)
+
+rnExpr (HsCase expr matches)
+ = rnLExpr expr `thenM` \ (new_expr, e_fvs) ->
+ rnMatchGroup CaseAlt matches `thenM` \ (new_matches, ms_fvs) ->
+ returnM (HsCase new_expr new_matches, e_fvs `plusFV` ms_fvs)
rnExpr (HsLet binds expr)
- = rnBinds binds $ \ binds' ->
- rnExpr expr `thenRn` \ (expr',fvExpr) ->
- returnRn (HsLet binds' expr', fvExpr)
-
-rnExpr e@(HsDo do_or_lc stmts src_loc)
- = pushSrcLocRn src_loc $
- lookupImplicitOccRn monadClass_RDR `thenRn` \ monad ->
- rnStmts rnExpr stmts `thenRn` \ (stmts', fvs) ->
- -- check the statement list ends in an expression
+ = rnBindGroupsAndThen binds $ \ binds' ->
+ rnLExpr expr `thenM` \ (expr',fvExpr) ->
+ returnM (HsLet binds' expr', fvExpr)
+
+rnExpr e@(HsDo do_or_lc stmts _ _)
+ = rnStmts do_or_lc stmts `thenM` \ (stmts', fvs) ->
+
+ -- Check the statement list ends in an expression
case last stmts' of {
- ExprStmt _ _ -> returnRn () ;
- ReturnStmt _ -> returnRn () ; -- for list comprehensions
- _ -> addErrRn (doStmtListErr e)
- } `thenRn_`
- returnRn (HsDo do_or_lc stmts' src_loc, fvs `addOneFV` monad)
-
-rnExpr (ExplicitList exps)
- = rnExprs exps `thenRn` \ (exps', fvs) ->
- returnRn (ExplicitList exps', fvs `addOneFV` listTyCon_name)
-
-rnExpr (ExplicitTuple exps boxed)
- = rnExprs exps `thenRn` \ (exps', fvs) ->
- returnRn (ExplicitTuple exps' boxed, fvs `addOneFV` tycon_name)
+ L _ (ResultStmt _) -> returnM () ;
+ other -> addLocErr other (doStmtListErr do_or_lc)
+ } `thenM_`
+
+ -- Generate the rebindable syntax for the monad
+ lookupSyntaxNames syntax_names `thenM` \ (syntax_names', monad_fvs) ->
+
+ returnM (HsDo do_or_lc stmts' syntax_names' placeHolderType, fvs `plusFV` monad_fvs)
+ where
+ syntax_names = case do_or_lc of
+ DoExpr -> monadNames
+ MDoExpr -> monadNames ++ [mfixName]
+ other -> []
+
+rnExpr (ExplicitList _ exps)
+ = rnExprs exps `thenM` \ (exps', fvs) ->
+ returnM (ExplicitList placeHolderType exps', fvs `addOneFV` listTyCon_name)
+
+rnExpr (ExplicitPArr _ exps)
+ = rnExprs exps `thenM` \ (exps', fvs) ->
+ returnM (ExplicitPArr placeHolderType exps', fvs)
+
+rnExpr e@(ExplicitTuple exps boxity)
+ = checkTupSize tup_size `thenM_`
+ rnExprs exps `thenM` \ (exps', fvs) ->
+ returnM (ExplicitTuple exps' boxity, fvs `addOneFV` tycon_name)
where
- tycon_name = tupleTyCon_name boxed (length exps)
+ tup_size = length exps
+ tycon_name = tupleTyCon_name boxity tup_size
rnExpr (RecordCon con_id rbinds)
- = lookupOccRn con_id `thenRn` \ conname ->
- rnRbinds "construction" rbinds `thenRn` \ (rbinds', fvRbinds) ->
- returnRn (RecordCon conname rbinds', fvRbinds `addOneFV` conname)
+ = lookupLocatedOccRn con_id `thenM` \ conname ->
+ rnRbinds "construction" rbinds `thenM` \ (rbinds', fvRbinds) ->
+ returnM (RecordCon conname rbinds', fvRbinds `addOneFV` unLoc conname)
rnExpr (RecordUpd expr rbinds)
- = rnExpr expr `thenRn` \ (expr', fvExpr) ->
- rnRbinds "update" rbinds `thenRn` \ (rbinds', fvRbinds) ->
- returnRn (RecordUpd expr' rbinds', fvExpr `plusFV` fvRbinds)
+ = rnLExpr expr `thenM` \ (expr', fvExpr) ->
+ rnRbinds "update" rbinds `thenM` \ (rbinds', fvRbinds) ->
+ returnM (RecordUpd expr' rbinds', fvExpr `plusFV` fvRbinds)
rnExpr (ExprWithTySig expr pty)
- = rnExpr expr `thenRn` \ (expr', fvExpr) ->
- rnHsSigType (text "an expression") pty `thenRn` \ (pty', fvTy) ->
- returnRn (ExprWithTySig expr' pty', fvExpr `plusFV` fvTy)
-
-rnExpr (HsIf p b1 b2 src_loc)
- = pushSrcLocRn src_loc $
- rnExpr p `thenRn` \ (p', fvP) ->
- rnExpr b1 `thenRn` \ (b1', fvB1) ->
- rnExpr b2 `thenRn` \ (b2', fvB2) ->
- returnRn (HsIf p' b1' b2' src_loc, plusFVs [fvP, fvB1, fvB2])
+ = rnLExpr expr `thenM` \ (expr', fvExpr) ->
+ rnHsTypeFVs doc pty `thenM` \ (pty', fvTy) ->
+ returnM (ExprWithTySig expr' pty', fvExpr `plusFV` fvTy)
+ where
+ doc = text "In an expression type signature"
+
+rnExpr (HsIf p b1 b2)
+ = rnLExpr p `thenM` \ (p', fvP) ->
+ rnLExpr b1 `thenM` \ (b1', fvB1) ->
+ rnLExpr b2 `thenM` \ (b2', fvB2) ->
+ returnM (HsIf p' b1' b2', plusFVs [fvP, fvB1, fvB2])
+
+rnExpr (HsType a)
+ = rnHsTypeFVs doc a `thenM` \ (t, fvT) ->
+ returnM (HsType t, fvT)
+ where
+ doc = text "In a type argument"
rnExpr (ArithSeqIn seq)
- = lookupImplicitOccRn enumClass_RDR `thenRn` \ enum ->
- rn_seq seq `thenRn` \ (new_seq, fvs) ->
- returnRn (ArithSeqIn new_seq, fvs `addOneFV` enum)
- where
- rn_seq (From expr)
- = rnExpr expr `thenRn` \ (expr', fvExpr) ->
- returnRn (From expr', fvExpr)
-
- rn_seq (FromThen expr1 expr2)
- = rnExpr expr1 `thenRn` \ (expr1', fvExpr1) ->
- rnExpr expr2 `thenRn` \ (expr2', fvExpr2) ->
- returnRn (FromThen expr1' expr2', fvExpr1 `plusFV` fvExpr2)
-
- rn_seq (FromTo expr1 expr2)
- = rnExpr expr1 `thenRn` \ (expr1', fvExpr1) ->
- rnExpr expr2 `thenRn` \ (expr2', fvExpr2) ->
- returnRn (FromTo expr1' expr2', fvExpr1 `plusFV` fvExpr2)
-
- rn_seq (FromThenTo expr1 expr2 expr3)
- = rnExpr expr1 `thenRn` \ (expr1', fvExpr1) ->
- rnExpr expr2 `thenRn` \ (expr2', fvExpr2) ->
- rnExpr expr3 `thenRn` \ (expr3', fvExpr3) ->
- returnRn (FromThenTo expr1' expr2' expr3',
- plusFVs [fvExpr1, fvExpr2, fvExpr3])
+ = rnArithSeq seq `thenM` \ (new_seq, fvs) ->
+ returnM (ArithSeqIn new_seq, fvs)
+
+rnExpr (PArrSeqIn seq)
+ = rnArithSeq seq `thenM` \ (new_seq, fvs) ->
+ returnM (PArrSeqIn new_seq, fvs)
\end{code}
These three are pattern syntax appearing in expressions.
We return a (bogus) EWildPat in each case.
\begin{code}
-rnExpr e@EWildPat = addErrRn (patSynErr e) `thenRn_`
- returnRn (EWildPat, emptyFVs)
+rnExpr e@EWildPat = addErr (patSynErr e) `thenM_`
+ returnM (EWildPat, emptyFVs)
-rnExpr e@(EAsPat _ _) = addErrRn (patSynErr e) `thenRn_`
- returnRn (EWildPat, emptyFVs)
+rnExpr e@(EAsPat _ _) = addErr (patSynErr e) `thenM_`
+ returnM (EWildPat, emptyFVs)
-rnExpr e@(ELazyPat _) = addErrRn (patSynErr e) `thenRn_`
- returnRn (EWildPat, emptyFVs)
+rnExpr e@(ELazyPat _) = addErr (patSynErr e) `thenM_`
+ returnM (EWildPat, emptyFVs)
\end{code}
%************************************************************************
%* *
-\subsubsection{@Rbinds@s and @Rpats@s: in record expressions}
+ Arrow notation
%* *
%************************************************************************
\begin{code}
-rnRbinds str rbinds
- = mapRn_ field_dup_err dup_fields `thenRn_`
- mapFvRn rn_rbind rbinds `thenRn` \ (rbinds', fvRbind) ->
- returnRn (rbinds', fvRbind)
+rnExpr (HsProc pat body)
+ = rnPatsAndThen ProcExpr True [pat] $ \ [pat'] ->
+ rnCmdTop body `thenM` \ (body',fvBody) ->
+ returnM (HsProc pat' body', fvBody)
+
+rnExpr (HsArrApp arrow arg _ ho rtl)
+ = rnLExpr arrow `thenM` \ (arrow',fvArrow) ->
+ rnLExpr arg `thenM` \ (arg',fvArg) ->
+ returnM (HsArrApp arrow' arg' placeHolderType ho rtl,
+ fvArrow `plusFV` fvArg)
+
+-- infix form
+rnExpr (HsArrForm op (Just _) [arg1, arg2])
+ = rnLExpr op `thenM` \ (op'@(L _ (HsVar op_name)),fv_op) ->
+ rnCmdTop arg1 `thenM` \ (arg1',fv_arg1) ->
+ rnCmdTop arg2 `thenM` \ (arg2',fv_arg2) ->
+
+ -- Deal with fixity
+
+ lookupFixityRn op_name `thenM` \ fixity ->
+ mkOpFormRn arg1' op' fixity arg2' `thenM` \ final_e ->
+
+ returnM (final_e,
+ fv_arg1 `plusFV` fv_op `plusFV` fv_arg2)
+
+rnExpr (HsArrForm op fixity cmds)
+ = rnLExpr op `thenM` \ (op',fvOp) ->
+ rnCmdArgs cmds `thenM` \ (cmds',fvCmds) ->
+ returnM (HsArrForm op' fixity cmds', fvOp `plusFV` fvCmds)
+
+---------------------------
+-- Deal with fixity (cf mkOpAppRn for the method)
+
+mkOpFormRn :: LHsCmdTop Name -- Left operand; already rearranged
+ -> LHsExpr Name -> Fixity -- Operator and fixity
+ -> LHsCmdTop Name -- Right operand (not an infix)
+ -> RnM (HsCmd Name)
+
+---------------------------
+-- (e11 `op1` e12) `op2` e2
+mkOpFormRn a1@(L loc (HsCmdTop (L _ (HsArrForm op1 (Just fix1) [a11,a12])) _ _ _))
+ op2 fix2 a2
+ | nofix_error
+ = addErr (precParseErr (ppr_op op1,fix1) (ppr_op op2,fix2)) `thenM_`
+ returnM (HsArrForm op2 (Just fix2) [a1, a2])
+
+ | associate_right
+ = mkOpFormRn a12 op2 fix2 a2 `thenM` \ new_c ->
+ returnM (HsArrForm op1 (Just fix1)
+ [a11, L loc (HsCmdTop (L loc new_c) [] placeHolderType [])])
+ -- TODO: locs are wrong
where
- (_, dup_fields) = removeDups compare [ f | (f,_,_) <- rbinds ]
+ (nofix_error, associate_right) = compareFixity fix1 fix2
+
+---------------------------
+-- Default case
+mkOpFormRn arg1 op fix arg2 -- Default case, no rearrangment
+ = returnM (HsArrForm op (Just fix) [arg1, arg2])
+
+\end{code}
+
+
+%************************************************************************
+%* *
+ Arrow commands
+%* *
+%************************************************************************
+
+\begin{code}
+rnCmdArgs [] = returnM ([], emptyFVs)
+rnCmdArgs (arg:args)
+ = rnCmdTop arg `thenM` \ (arg',fvArg) ->
+ rnCmdArgs args `thenM` \ (args',fvArgs) ->
+ returnM (arg':args', fvArg `plusFV` fvArgs)
+
+
+rnCmdTop = wrapLocFstM rnCmdTop'
+ where
+ rnCmdTop' (HsCmdTop cmd _ _ _)
+ = rnLExpr (convertOpFormsLCmd cmd) `thenM` \ (cmd', fvCmd) ->
+ let
+ cmd_names = [arrAName, composeAName, firstAName] ++
+ nameSetToList (methodNamesCmd (unLoc cmd'))
+ in
+ -- Generate the rebindable syntax for the monad
+ lookupSyntaxNames cmd_names `thenM` \ (cmd_names', cmd_fvs) ->
+
+ returnM (HsCmdTop cmd' [] placeHolderType cmd_names',
+ fvCmd `plusFV` cmd_fvs)
+
+---------------------------------------------------
+-- convert OpApp's in a command context to HsArrForm's
+
+convertOpFormsLCmd :: LHsCmd id -> LHsCmd id
+convertOpFormsLCmd = fmap convertOpFormsCmd
+
+convertOpFormsCmd :: HsCmd id -> HsCmd id
+
+convertOpFormsCmd (HsApp c e) = HsApp (convertOpFormsLCmd c) e
+convertOpFormsCmd (HsLam match) = HsLam (convertOpFormsMatch match)
+convertOpFormsCmd (OpApp c1 op fixity c2)
+ = let
+ arg1 = L (getLoc c1) $ HsCmdTop (convertOpFormsLCmd c1) [] placeHolderType []
+ arg2 = L (getLoc c2) $ HsCmdTop (convertOpFormsLCmd c2) [] placeHolderType []
+ in
+ HsArrForm op (Just fixity) [arg1, arg2]
+
+convertOpFormsCmd (HsPar c) = HsPar (convertOpFormsLCmd c)
+
+-- gaw 2004
+convertOpFormsCmd (HsCase exp matches)
+ = HsCase exp (convertOpFormsMatch matches)
+
+convertOpFormsCmd (HsIf exp c1 c2)
+ = HsIf exp (convertOpFormsLCmd c1) (convertOpFormsLCmd c2)
+
+convertOpFormsCmd (HsLet binds cmd)
+ = HsLet binds (convertOpFormsLCmd cmd)
+
+convertOpFormsCmd (HsDo ctxt stmts ids ty)
+ = HsDo ctxt (map (fmap convertOpFormsStmt) stmts) ids ty
+
+-- Anything else is unchanged. This includes HsArrForm (already done),
+-- things with no sub-commands, and illegal commands (which will be
+-- caught by the type checker)
+convertOpFormsCmd c = c
+
+convertOpFormsStmt (BindStmt pat cmd)
+ = BindStmt pat (convertOpFormsLCmd cmd)
+convertOpFormsStmt (ResultStmt cmd)
+ = ResultStmt (convertOpFormsLCmd cmd)
+convertOpFormsStmt (ExprStmt cmd ty)
+ = ExprStmt (convertOpFormsLCmd cmd) ty
+convertOpFormsStmt (RecStmt stmts lvs rvs es)
+ = RecStmt (map (fmap convertOpFormsStmt) stmts) lvs rvs es
+convertOpFormsStmt stmt = stmt
- field_dup_err dups = addErrRn (dupFieldErr str dups)
+convertOpFormsMatch (MatchGroup ms ty)
+ = MatchGroup (map (fmap convert) ms) ty
+ where convert (Match pat mty grhss)
+ = Match pat mty (convertOpFormsGRHSs grhss)
- rn_rbind (field, expr, pun)
- = lookupGlobalOccRn field `thenRn` \ fieldname ->
- rnExpr expr `thenRn` \ (expr', fvExpr) ->
- returnRn ((fieldname, expr', pun), fvExpr `addOneFV` fieldname)
+convertOpFormsGRHSs (GRHSs grhss binds)
+ = GRHSs (map convertOpFormsGRHS grhss) binds
-rnRpats rpats
- = mapRn_ field_dup_err dup_fields `thenRn_`
- mapFvRn rn_rpat rpats `thenRn` \ (rpats', fvs) ->
- returnRn (rpats', fvs)
+convertOpFormsGRHS = fmap convert
+ where convert (GRHS stmts)
+ = let
+ (L loc (ResultStmt cmd)) = last stmts
+ in
+ GRHS (init stmts ++ [L loc (ResultStmt (convertOpFormsLCmd cmd))])
+
+---------------------------------------------------
+type CmdNeeds = FreeVars -- Only inhabitants are
+ -- appAName, choiceAName, loopAName
+
+-- find what methods the Cmd needs (loop, choice, apply)
+methodNamesLCmd :: LHsCmd Name -> CmdNeeds
+methodNamesLCmd = methodNamesCmd . unLoc
+
+methodNamesCmd :: HsCmd Name -> CmdNeeds
+
+methodNamesCmd cmd@(HsArrApp _arrow _arg _ HsFirstOrderApp _rtl)
+ = emptyFVs
+methodNamesCmd cmd@(HsArrApp _arrow _arg _ HsHigherOrderApp _rtl)
+ = unitFV appAName
+methodNamesCmd cmd@(HsArrForm {}) = emptyFVs
+
+methodNamesCmd (HsPar c) = methodNamesLCmd c
+
+methodNamesCmd (HsIf p c1 c2)
+ = methodNamesLCmd c1 `plusFV` methodNamesLCmd c2 `addOneFV` choiceAName
+
+methodNamesCmd (HsLet b c) = methodNamesLCmd c
+
+methodNamesCmd (HsDo sc stmts rbs ty) = methodNamesStmts stmts
+
+methodNamesCmd (HsApp c e) = methodNamesLCmd c
+
+methodNamesCmd (HsLam match) = methodNamesMatch match
+
+methodNamesCmd (HsCase scrut matches)
+ = methodNamesMatch matches `addOneFV` choiceAName
+
+methodNamesCmd other = emptyFVs
+ -- Other forms can't occur in commands, but it's not convenient
+ -- to error here so we just do what's convenient.
+ -- The type checker will complain later
+
+---------------------------------------------------
+methodNamesMatch (MatchGroup ms ty)
+ = plusFVs (map do_one ms)
+ where
+ do_one (L _ (Match pats sig_ty grhss)) = methodNamesGRHSs grhss
+
+-------------------------------------------------
+-- gaw 2004
+methodNamesGRHSs (GRHSs grhss binds) = plusFVs (map methodNamesGRHS grhss)
+
+-------------------------------------------------
+methodNamesGRHS (L _ (GRHS stmts)) = methodNamesLStmt (last stmts)
+
+---------------------------------------------------
+methodNamesStmts stmts = plusFVs (map methodNamesLStmt stmts)
+
+---------------------------------------------------
+methodNamesLStmt = methodNamesStmt . unLoc
+
+methodNamesStmt (ResultStmt cmd) = methodNamesLCmd cmd
+methodNamesStmt (ExprStmt cmd ty) = methodNamesLCmd cmd
+methodNamesStmt (BindStmt pat cmd ) = methodNamesLCmd cmd
+methodNamesStmt (RecStmt stmts lvs rvs es)
+ = methodNamesStmts stmts `addOneFV` loopAName
+methodNamesStmt (LetStmt b) = emptyFVs
+methodNamesStmt (ParStmt ss) = emptyFVs
+ -- ParStmt can't occur in commands, but it's not convenient to error
+ -- here so we just do what's convenient
+\end{code}
+
+
+%************************************************************************
+%* *
+ Arithmetic sequences
+%* *
+%************************************************************************
+
+\begin{code}
+rnArithSeq (From expr)
+ = rnLExpr expr `thenM` \ (expr', fvExpr) ->
+ returnM (From expr', fvExpr)
+
+rnArithSeq (FromThen expr1 expr2)
+ = rnLExpr expr1 `thenM` \ (expr1', fvExpr1) ->
+ rnLExpr expr2 `thenM` \ (expr2', fvExpr2) ->
+ returnM (FromThen expr1' expr2', fvExpr1 `plusFV` fvExpr2)
+
+rnArithSeq (FromTo expr1 expr2)
+ = rnLExpr expr1 `thenM` \ (expr1', fvExpr1) ->
+ rnLExpr expr2 `thenM` \ (expr2', fvExpr2) ->
+ returnM (FromTo expr1' expr2', fvExpr1 `plusFV` fvExpr2)
+
+rnArithSeq (FromThenTo expr1 expr2 expr3)
+ = rnLExpr expr1 `thenM` \ (expr1', fvExpr1) ->
+ rnLExpr expr2 `thenM` \ (expr2', fvExpr2) ->
+ rnLExpr expr3 `thenM` \ (expr3', fvExpr3) ->
+ returnM (FromThenTo expr1' expr2' expr3',
+ plusFVs [fvExpr1, fvExpr2, fvExpr3])
+\end{code}
+
+
+%************************************************************************
+%* *
+\subsubsection{@Rbinds@s and @Rpats@s: in record expressions}
+%* *
+%************************************************************************
+
+\begin{code}
+rnRbinds str rbinds
+ = mappM_ field_dup_err dup_fields `thenM_`
+ mapFvRn rn_rbind rbinds `thenM` \ (rbinds', fvRbind) ->
+ returnM (rbinds', fvRbind)
where
- (_, dup_fields) = removeDups compare [ f | (f,_,_) <- rpats ]
+ (_, dup_fields) = removeDups cmpLocated [ f | (f,_) <- rbinds ]
- field_dup_err dups = addErrRn (dupFieldErr "pattern" dups)
+ field_dup_err dups = mappM_ (\f -> addLocErr f (dupFieldErr str)) dups
- rn_rpat (field, pat, pun)
- = lookupGlobalOccRn field `thenRn` \ fieldname ->
- rnPat pat `thenRn` \ (pat', fvs) ->
- returnRn ((fieldname, pat', pun), fvs `addOneFV` fieldname)
+ rn_rbind (field, expr)
+ = lookupLocatedGlobalOccRn field `thenM` \ fieldname ->
+ rnLExpr expr `thenM` \ (expr', fvExpr) ->
+ returnM ((fieldname, expr'), fvExpr `addOneFV` unLoc fieldname)
+\end{code}
+
+%************************************************************************
+%* *
+ Template Haskell brackets
+%* *
+%************************************************************************
+
+\begin{code}
+rnBracket (VarBr n) = lookupOccRn n `thenM` \ name ->
+ returnM (VarBr name, unitFV name)
+rnBracket (ExpBr e) = rnLExpr e `thenM` \ (e', fvs) ->
+ returnM (ExpBr e', fvs)
+rnBracket (PatBr p) = rnLPat p `thenM` \ (p', fvs) ->
+ returnM (PatBr p', fvs)
+rnBracket (TypBr t) = rnHsTypeFVs doc t `thenM` \ (t', fvs) ->
+ returnM (TypBr t', fvs)
+ where
+ doc = ptext SLIT("In a Template-Haskell quoted type")
+rnBracket (DecBr group)
+ = importsFromLocalDecls group `thenM` \ (rdr_env, avails) ->
+ -- Discard avails (not useful here)
+
+ updGblEnv (\gbl -> gbl { tcg_rdr_env = tcg_rdr_env gbl `plusOccEnv` rdr_env}) $
+ -- Notice plusOccEnv, not plusGlobalRdrEnv. In this situation we want
+ -- to *shadow* top-level bindings. E.g.
+ -- foo = 1
+ -- bar = [d| foo = 1|]
+ -- So we drop down to plusOccEnv. (Perhaps there should be a fn in RdrName.)
+
+ rnSrcDecls group `thenM` \ (tcg_env, group') ->
+ -- Discard the tcg_env; it contains only extra info about fixity
+ let
+ dus = tcg_dus tcg_env
+ in
+ returnM (DecBr group', allUses dus)
\end{code}
%************************************************************************
%* *
%************************************************************************
-Note that although some bound vars may appear in the free var set for
-the first qual, these will eventually be removed by the caller. For
-example, if we have @[p | r <- s, q <- r, p <- q]@, when doing
-@[q <- r, p <- q]@, the free var set for @q <- r@ will
-be @{r}@, and the free var set for the entire Quals will be @{r}@. This
-@r@ will be removed only when we finally return from examining all the
-Quals.
+\begin{code}
+rnStmts :: HsStmtContext Name -> [LStmt RdrName] -> RnM ([LStmt Name], FreeVars)
+
+rnStmts MDoExpr = rnMDoStmts
+rnStmts ctxt = rnNormalStmts ctxt
+
+rnNormalStmts :: HsStmtContext Name -> [LStmt RdrName] -> RnM ([LStmt Name], FreeVars)
+-- Used for cases *other* than recursive mdo
+-- Implements nested scopes
+
+rnNormalStmts ctxt [] = returnM ([], emptyFVs)
+ -- Happens at the end of the sub-lists of a ParStmts
+
+rnNormalStmts ctxt (L loc (ExprStmt expr _) : stmts)
+ = rnLExpr expr `thenM` \ (expr', fv_expr) ->
+ rnNormalStmts ctxt stmts `thenM` \ (stmts', fvs) ->
+ returnM (L loc (ExprStmt expr' placeHolderType) : stmts',
+ fv_expr `plusFV` fvs)
+
+rnNormalStmts ctxt [L loc (ResultStmt expr)]
+ = rnLExpr expr `thenM` \ (expr', fv_expr) ->
+ returnM ([L loc (ResultStmt expr')], fv_expr)
+
+rnNormalStmts ctxt (L loc (BindStmt pat expr) : stmts)
+ = rnLExpr expr `thenM` \ (expr', fv_expr) ->
+ -- The binders do not scope over the expression
+
+ let
+ reportUnused =
+ case ctxt of
+ ParStmtCtxt{} -> False
+ _ -> True
+ in
+ rnPatsAndThen (StmtCtxt ctxt) reportUnused [pat] $ \ [pat'] ->
+ rnNormalStmts ctxt stmts `thenM` \ (stmts', fvs) ->
+ returnM (L loc (BindStmt pat' expr') : stmts',
+ fv_expr `plusFV` fvs) -- fv_expr shouldn't really be filtered by
+ -- the rnPatsAndThen, but it does not matter
+
+rnNormalStmts ctxt (L loc (LetStmt binds) : stmts)
+ = checkErr (ok ctxt binds) (badIpBinds binds) `thenM_`
+ rnBindGroupsAndThen binds ( \ binds' ->
+ rnNormalStmts ctxt stmts `thenM` \ (stmts', fvs) ->
+ returnM (L loc (LetStmt binds') : stmts', fvs))
+ where
+ -- We do not allow implicit-parameter bindings in a parallel
+ -- list comprehension. I'm not sure what it might mean.
+ ok (ParStmtCtxt _) binds = not (any is_ip_bind binds)
+ ok _ _ = True
+
+ is_ip_bind (HsIPBinds _) = True
+ is_ip_bind _ = False
+
+rnNormalStmts ctxt (L loc (ParStmt stmtss) : stmts)
+ = doptM Opt_GlasgowExts `thenM` \ opt_GlasgowExts ->
+ checkM opt_GlasgowExts parStmtErr `thenM_`
+ mapFvRn rn_branch stmtss `thenM` \ (stmtss', fv_stmtss) ->
+ let
+ bndrss :: [[Name]] -- NB: Name, not RdrName
+ bndrss = map (map unLoc . collectStmtsBinders) stmtss'
+ (bndrs, dups) = removeDups cmpByOcc (concat bndrss)
+ in
+ mappM dupErr dups `thenM` \ _ ->
+ bindLocalNamesFV bndrs $
+ -- Note: binders are returned in scope order, so one may
+ -- shadow the next; e.g. x <- xs; x <- ys
+ rnNormalStmts ctxt stmts `thenM` \ (stmts', fvs) ->
+
+ -- Cut down the exported binders to just the ones needed in the body
+ let
+ used_bndrs_s = map (filter (`elemNameSet` fvs)) bndrss
+ unused_bndrs = filter (not . (`elemNameSet` fvs)) bndrs
+ in
+ -- With processing of the branches and the tail of comprehension done,
+ -- we can finally compute&report any unused ParStmt binders.
+ warnUnusedMatches unused_bndrs `thenM_`
+ returnM (L loc (ParStmt (stmtss' `zip` used_bndrs_s)) : stmts',
+ fv_stmtss `plusFV` fvs)
+ where
+ rn_branch (stmts, _) = rnNormalStmts (ParStmtCtxt ctxt) stmts
+
+ cmpByOcc n1 n2 = nameOccName n1 `compare` nameOccName n2
+ dupErr (v:_) = addErr (ptext SLIT("Duplicate binding in parallel list comprehension for:")
+ <+> quotes (ppr v))
+
+rnNormalStmts ctxt (L loc (RecStmt rec_stmts _ _ _) : stmts)
+ = bindLocatedLocalsRn doc (collectStmtsBinders rec_stmts) $ \ _ ->
+ rn_rec_stmts rec_stmts `thenM` \ segs ->
+ rnNormalStmts ctxt stmts `thenM` \ (stmts', fvs) ->
+ let
+ segs_w_fwd_refs = addFwdRefs segs
+ (ds, us, fs, rec_stmts') = unzip4 segs_w_fwd_refs
+ later_vars = nameSetToList (plusFVs ds `intersectNameSet` fvs)
+ fwd_vars = nameSetToList (plusFVs fs)
+ uses = plusFVs us
+ in
+ returnM (L loc (RecStmt rec_stmts' later_vars fwd_vars []) : stmts',
+ uses `plusFV` fvs)
+ where
+ doc = text "In a recursive do statement"
+\end{code}
+
+
+%************************************************************************
+%* *
+\subsubsection{mdo expressions}
+%* *
+%************************************************************************
\begin{code}
-type RnExprTy = RdrNameHsExpr -> RnMS (RenamedHsExpr, FreeVars)
-
-rnStmts :: RnExprTy
- -> [RdrNameStmt]
- -> RnMS ([RenamedStmt], FreeVars)
-
-rnStmts rn_expr []
- = returnRn ([], emptyFVs)
-
-rnStmts rn_expr (stmt:stmts)
- = rnStmt rn_expr stmt $ \ stmt' ->
- rnStmts rn_expr stmts `thenRn` \ (stmts', fvs) ->
- returnRn (stmt' : stmts', fvs)
-
-rnStmt :: RnExprTy -> RdrNameStmt
- -> (RenamedStmt -> RnMS (a, FreeVars))
- -> RnMS (a, FreeVars)
--- Because of mutual recursion we have to pass in rnExpr.
-
-rnStmt rn_expr (BindStmt pat expr src_loc) thing_inside
- = pushSrcLocRn src_loc $
- rn_expr expr `thenRn` \ (expr', fv_expr) ->
- bindLocalsFVRn doc binders $ \ new_binders ->
- rnPat pat `thenRn` \ (pat', fv_pat) ->
- thing_inside (BindStmt pat' expr' src_loc) `thenRn` \ (result, fvs) ->
- returnRn (result, fv_expr `plusFV` fvs `plusFV` fv_pat)
+type FwdRefs = NameSet
+type Segment stmts = (Defs,
+ Uses, -- May include defs
+ FwdRefs, -- A subset of uses that are
+ -- (a) used before they are bound in this segment, or
+ -- (b) used here, and bound in subsequent segments
+ stmts) -- Either Stmt or [Stmt]
+
+
+----------------------------------------------------
+rnMDoStmts :: [LStmt RdrName] -> RnM ([LStmt Name], FreeVars)
+rnMDoStmts stmts
+ = -- Step1: bring all the binders of the mdo into scope
+ -- Remember that this also removes the binders from the
+ -- finally-returned free-vars
+ bindLocatedLocalsRn doc (collectStmtsBinders stmts) $ \ _ ->
+
+ -- Step 2: Rename each individual stmt, making a
+ -- singleton segment. At this stage the FwdRefs field
+ -- isn't finished: it's empty for all except a BindStmt
+ -- for which it's the fwd refs within the bind itself
+ -- (This set may not be empty, because we're in a recursive
+ -- context.)
+ rn_rec_stmts stmts `thenM` \ segs ->
+ let
+ -- Step 3: Fill in the fwd refs.
+ -- The segments are all singletons, but their fwd-ref
+ -- field mentions all the things used by the segment
+ -- that are bound after their use
+ segs_w_fwd_refs = addFwdRefs segs
+
+ -- Step 4: Group together the segments to make bigger segments
+ -- Invariant: in the result, no segment uses a variable
+ -- bound in a later segment
+ grouped_segs = glomSegments segs_w_fwd_refs
+
+ -- Step 5: Turn the segments into Stmts
+ -- Use RecStmt when and only when there are fwd refs
+ -- Also gather up the uses from the end towards the
+ -- start, so we can tell the RecStmt which things are
+ -- used 'after' the RecStmt
+ stmts_w_fvs = segsToStmts grouped_segs
+ in
+ returnM stmts_w_fvs
+ where
+
+ doc = text "In a recursive mdo-expression"
+
+
+----------------------------------------------------
+rn_rec_stmt :: LStmt RdrName -> RnM [Segment (LStmt Name)]
+ -- Rename a Stmt that is inside a RecStmt (or mdo)
+ -- Assumes all binders are already in scope
+ -- Turns each stmt into a singleton Stmt
+
+rn_rec_stmt (L loc (ExprStmt expr _))
+ = rnLExpr expr `thenM` \ (expr', fvs) ->
+ returnM [(emptyNameSet, fvs, emptyNameSet,
+ L loc (ExprStmt expr' placeHolderType))]
+
+rn_rec_stmt (L loc (ResultStmt expr))
+ = rnLExpr expr `thenM` \ (expr', fvs) ->
+ returnM [(emptyNameSet, fvs, emptyNameSet,
+ L loc (ResultStmt expr'))]
+
+rn_rec_stmt (L loc (BindStmt pat expr))
+ = rnLExpr expr `thenM` \ (expr', fv_expr) ->
+ rnLPat pat `thenM` \ (pat', fv_pat) ->
+ let
+ bndrs = mkNameSet (collectPatBinders pat')
+ fvs = fv_expr `plusFV` fv_pat
+ in
+ returnM [(bndrs, fvs, bndrs `intersectNameSet` fvs,
+ L loc (BindStmt pat' expr'))]
+
+rn_rec_stmt (L loc (LetStmt binds))
+ = rnBindGroups binds `thenM` \ (binds', du_binds) ->
+ returnM [(duDefs du_binds, duUses du_binds,
+ emptyNameSet, L loc (LetStmt binds'))]
+
+rn_rec_stmt (L loc (RecStmt stmts _ _ _)) -- Flatten Rec inside Rec
+ = rn_rec_stmts stmts
+
+rn_rec_stmt stmt@(L _ (ParStmt _)) -- Syntactically illegal in mdo
+ = pprPanic "rn_rec_stmt" (ppr stmt)
+
+---------------------------------------------
+rn_rec_stmts :: [LStmt RdrName] -> RnM [Segment (LStmt Name)]
+rn_rec_stmts stmts = mappM rn_rec_stmt stmts `thenM` \ segs_s ->
+ returnM (concat segs_s)
+
+
+---------------------------------------------
+addFwdRefs :: [Segment a] -> [Segment a]
+-- So far the segments only have forward refs *within* the Stmt
+-- (which happens for bind: x <- ...x...)
+-- This function adds the cross-seg fwd ref info
+
+addFwdRefs pairs
+ = fst (foldr mk_seg ([], emptyNameSet) pairs)
where
- binders = collectPatBinders pat
- doc = text "a pattern in do binding"
-
-rnStmt rn_expr (ExprStmt expr src_loc) thing_inside
- = pushSrcLocRn src_loc $
- rn_expr expr `thenRn` \ (expr', fv_expr) ->
- thing_inside (ExprStmt expr' src_loc) `thenRn` \ (result, fvs) ->
- returnRn (result, fv_expr `plusFV` fvs)
-
-rnStmt rn_expr (GuardStmt expr src_loc) thing_inside
- = pushSrcLocRn src_loc $
- rn_expr expr `thenRn` \ (expr', fv_expr) ->
- thing_inside (GuardStmt expr' src_loc) `thenRn` \ (result, fvs) ->
- returnRn (result, fv_expr `plusFV` fvs)
-
-rnStmt rn_expr (ReturnStmt expr) thing_inside
- = rn_expr expr `thenRn` \ (expr', fv_expr) ->
- thing_inside (ReturnStmt expr') `thenRn` \ (result, fvs) ->
- returnRn (result, fv_expr `plusFV` fvs)
-
-rnStmt rn_expr (LetStmt binds) thing_inside
- = rnBinds binds $ \ binds' ->
- thing_inside (LetStmt binds')
+ mk_seg (defs, uses, fwds, stmts) (segs, later_defs)
+ = (new_seg : segs, all_defs)
+ where
+ new_seg = (defs, uses, new_fwds, stmts)
+ all_defs = later_defs `unionNameSets` defs
+ new_fwds = fwds `unionNameSets` (uses `intersectNameSet` later_defs)
+ -- Add the downstream fwd refs here
+
+----------------------------------------------------
+-- Glomming the singleton segments of an mdo into
+-- minimal recursive groups.
+--
+-- At first I thought this was just strongly connected components, but
+-- there's an important constraint: the order of the stmts must not change.
+--
+-- Consider
+-- mdo { x <- ...y...
+-- p <- z
+-- y <- ...x...
+-- q <- x
+-- z <- y
+-- r <- x }
+--
+-- Here, the first stmt mention 'y', which is bound in the third.
+-- But that means that the innocent second stmt (p <- z) gets caught
+-- up in the recursion. And that in turn means that the binding for
+-- 'z' has to be included... and so on.
+--
+-- Start at the tail { r <- x }
+-- Now add the next one { z <- y ; r <- x }
+-- Now add one more { q <- x ; z <- y ; r <- x }
+-- Now one more... but this time we have to group a bunch into rec
+-- { rec { y <- ...x... ; q <- x ; z <- y } ; r <- x }
+-- Now one more, which we can add on without a rec
+-- { p <- z ;
+-- rec { y <- ...x... ; q <- x ; z <- y } ;
+-- r <- x }
+-- Finally we add the last one; since it mentions y we have to
+-- glom it togeher with the first two groups
+-- { rec { x <- ...y...; p <- z ; y <- ...x... ;
+-- q <- x ; z <- y } ;
+-- r <- x }
+
+glomSegments :: [Segment (LStmt Name)] -> [Segment [LStmt Name]]
+
+glomSegments [] = []
+glomSegments ((defs,uses,fwds,stmt) : segs)
+ -- Actually stmts will always be a singleton
+ = (seg_defs, seg_uses, seg_fwds, seg_stmts) : others
+ where
+ segs' = glomSegments segs
+ (extras, others) = grab uses segs'
+ (ds, us, fs, ss) = unzip4 extras
+
+ seg_defs = plusFVs ds `plusFV` defs
+ seg_uses = plusFVs us `plusFV` uses
+ seg_fwds = plusFVs fs `plusFV` fwds
+ seg_stmts = stmt : concat ss
+
+ grab :: NameSet -- The client
+ -> [Segment a]
+ -> ([Segment a], -- Needed by the 'client'
+ [Segment a]) -- Not needed by the client
+ -- The result is simply a split of the input
+ grab uses dus
+ = (reverse yeses, reverse noes)
+ where
+ (noes, yeses) = span not_needed (reverse dus)
+ not_needed (defs,_,_,_) = not (intersectsNameSet defs uses)
+
+
+----------------------------------------------------
+segsToStmts :: [Segment [LStmt Name]] -> ([LStmt Name], FreeVars)
+
+segsToStmts [] = ([], emptyFVs)
+segsToStmts ((defs, uses, fwds, ss) : segs)
+ = ASSERT( not (null ss) )
+ (new_stmt : later_stmts, later_uses `plusFV` uses)
+ where
+ (later_stmts, later_uses) = segsToStmts segs
+ new_stmt | non_rec = head ss
+ | otherwise = L (getLoc (head ss)) $
+ RecStmt ss (nameSetToList used_later) (nameSetToList fwds) []
+ where
+ non_rec = isSingleton ss && isEmptyNameSet fwds
+ used_later = defs `intersectNameSet` later_uses
+ -- The ones needed after the RecStmt
\end{code}
%************************************************************************
we need to handle specially.
\begin{code}
-mkOpAppRn :: RenamedHsExpr -- Left operand; already rearranged
- -> RenamedHsExpr -> Fixity -- Operator and fixity
- -> RenamedHsExpr -- Right operand (not an OpApp, but might
+mkOpAppRn :: LHsExpr Name -- Left operand; already rearranged
+ -> LHsExpr Name -> Fixity -- Operator and fixity
+ -> LHsExpr Name -- Right operand (not an OpApp, but might
-- be a NegApp)
- -> RnMS RenamedHsExpr
+ -> RnM (HsExpr Name)
---------------------------
-- (e11 `op1` e12) `op2` e2
-mkOpAppRn e1@(OpApp e11 op1 fix1 e12) op2 fix2 e2
+mkOpAppRn e1@(L _ (OpApp e11 op1 fix1 e12)) op2 fix2 e2
| nofix_error
- = addErrRn (precParseErr (ppr_op op1,fix1) (ppr_op op2,fix2)) `thenRn_`
- returnRn (OpApp e1 op2 fix2 e2)
+ = addErr (precParseErr (ppr_op op1,fix1) (ppr_op op2,fix2)) `thenM_`
+ returnM (OpApp e1 op2 fix2 e2)
| associate_right
- = mkOpAppRn e12 op2 fix2 e2 `thenRn` \ new_e ->
- returnRn (OpApp e11 op1 fix1 new_e)
+ = mkOpAppRn e12 op2 fix2 e2 `thenM` \ new_e ->
+ returnM (OpApp e11 op1 fix1 (L loc' new_e))
where
+ loc'= combineLocs e12 e2
(nofix_error, associate_right) = compareFixity fix1 fix2
---------------------------
-- (- neg_arg) `op` e2
-mkOpAppRn e1@(NegApp neg_arg neg_op) op2 fix2 e2
+mkOpAppRn e1@(L _ (NegApp neg_arg neg_name)) op2 fix2 e2
| nofix_error
- = addErrRn (precParseErr (pp_prefix_minus,negateFixity) (ppr_op op2,fix2)) `thenRn_`
- returnRn (OpApp e1 op2 fix2 e2)
+ = addErr (precParseErr (pp_prefix_minus,negateFixity) (ppr_op op2,fix2)) `thenM_`
+ returnM (OpApp e1 op2 fix2 e2)
| associate_right
- = mkOpAppRn neg_arg op2 fix2 e2 `thenRn` \ new_e ->
- returnRn (NegApp new_e neg_op)
+ = mkOpAppRn neg_arg op2 fix2 e2 `thenM` \ new_e ->
+ returnM (NegApp (L loc' new_e) neg_name)
where
+ loc' = combineLocs neg_arg e2
(nofix_error, associate_right) = compareFixity negateFixity fix2
---------------------------
-- e1 `op` - neg_arg
-mkOpAppRn e1 op1 fix1 e2@(NegApp neg_arg neg_op) -- NegApp can occur on the right
- | not associate_right -- We *want* right association
- = addErrRn (precParseErr (ppr_op op1, fix1) (pp_prefix_minus, negateFixity)) `thenRn_`
- returnRn (OpApp e1 op1 fix1 e2)
+mkOpAppRn e1 op1 fix1 e2@(L _ (NegApp neg_arg _)) -- NegApp can occur on the right
+ | not associate_right -- We *want* right association
+ = addErr (precParseErr (ppr_op op1, fix1) (pp_prefix_minus, negateFixity)) `thenM_`
+ returnM (OpApp e1 op1 fix1 e2)
where
- (nofix_err, associate_right) = compareFixity fix1 negateFixity
+ (_, associate_right) = compareFixity fix1 negateFixity
---------------------------
-- Default case
mkOpAppRn e1 op fix e2 -- Default case, no rearrangment
- = ASSERT2( right_op_ok fix e2,
+ = ASSERT2( right_op_ok fix (unLoc e2),
ppr e1 $$ text "---" $$ ppr op $$ text "---" $$ ppr fix $$ text "---" $$ ppr e2
)
- returnRn (OpApp e1 op fix e2)
+ returnM (OpApp e1 op fix e2)
-- Parser left-associates everything, but
-- derived instances may have correctly-associated things to
= True
-- Parser initially makes negation bind more tightly than any other operator
-mkNegAppRn neg_arg neg_op
- =
-#ifdef DEBUG
- getModeRn `thenRn` \ mode ->
- ASSERT( not_op_app mode neg_arg )
-#endif
- returnRn (NegApp neg_arg neg_op)
-
-not_op_app SourceMode (OpApp _ _ _ _) = False
-not_op_app mode other = True
+-- And "deriving" code should respect this (use HsPar if not)
+mkNegAppRn :: LHsExpr id -> SyntaxName -> RnM (HsExpr id)
+mkNegAppRn neg_arg neg_name
+ = ASSERT( not_op_app (unLoc neg_arg) )
+ returnM (NegApp neg_arg neg_name)
+
+not_op_app (OpApp _ _ _ _) = False
+not_op_app other = True
\end{code}
\begin{code}
-mkConOpPatRn :: RenamedPat -> Name -> Fixity -> RenamedPat
- -> RnMS RenamedPat
-
-mkConOpPatRn p1@(ConOpPatIn p11 op1 fix1 p12)
- op2 fix2 p2
- | nofix_error
- = addErrRn (precParseErr (ppr_op op1,fix1) (ppr_op op2,fix2)) `thenRn_`
- returnRn (ConOpPatIn p1 op2 fix2 p2)
-
- | associate_right
- = mkConOpPatRn p12 op2 fix2 p2 `thenRn` \ new_p ->
- returnRn (ConOpPatIn p11 op1 fix1 new_p)
-
+checkPrecMatch :: Bool -> Name -> MatchGroup Name -> RnM ()
+ -- True indicates an infix lhs
+ -- See comments with rnExpr (OpApp ...) about "deriving"
+
+checkPrecMatch False fn match
+ = returnM ()
+checkPrecMatch True op (MatchGroup ms _)
+ = mapM_ check ms
where
- (nofix_error, associate_right) = compareFixity fix1 fix2
-
-mkConOpPatRn p1@(NegPatIn neg_arg)
- op2
- fix2@(Fixity prec2 dir2)
- p2
- | prec2 > negatePrecedence -- Precedence of unary - is wired in
- = addErrRn (precParseNegPatErr (ppr_op op2,fix2)) `thenRn_`
- returnRn (ConOpPatIn p1 op2 fix2 p2)
-
-mkConOpPatRn p1 op fix p2 -- Default case, no rearrangment
- = ASSERT( not_op_pat p2 )
- returnRn (ConOpPatIn p1 op fix p2)
-
-not_op_pat (ConOpPatIn _ _ _ _) = False
-not_op_pat other = True
-\end{code}
+ check (L _ (Match (p1:p2:_) _ _))
+ = checkPrec op (unLoc p1) False `thenM_`
+ checkPrec op (unLoc p2) True
-\begin{code}
-checkPrecMatch :: Bool -> Name -> RenamedMatch -> RnMS ()
-
-checkPrecMatch False fn match
- = returnRn ()
-
-checkPrecMatch True op (Match _ [p1,p2] _ _)
- = getModeRn `thenRn` \ mode ->
- -- See comments with rnExpr (OpApp ...)
- case mode of
- InterfaceMode -> returnRn ()
- SourceMode -> checkPrec op p1 False `thenRn_`
- checkPrec op p2 True
-
-checkPrecMatch True op _ = panic "checkPrecMatch"
+ check _ = panic "checkPrecMatch"
-checkPrec op (ConOpPatIn _ op1 _ _) right
- = lookupFixity op `thenRn` \ op_fix@(Fixity op_prec op_dir) ->
- lookupFixity op1 `thenRn` \ op1_fix@(Fixity op1_prec op1_dir) ->
+checkPrec op (ConPatIn op1 (InfixCon _ _)) right
+ = lookupFixityRn op `thenM` \ op_fix@(Fixity op_prec op_dir) ->
+ lookupFixityRn (unLoc op1) `thenM` \ op1_fix@(Fixity op1_prec op1_dir) ->
let
inf_ok = op1_prec > op_prec ||
(op1_prec == op_prec &&
info1 = (ppr_op op1, op1_fix)
(infol, infor) = if right then (info, info1) else (info1, info)
in
- checkRn inf_ok (precParseErr infol infor)
-
-checkPrec op (NegPatIn _) right
- = lookupFixity op `thenRn` \ op_fix@(Fixity op_prec op_dir) ->
- checkRn (op_prec <= negatePrecedence) (precParseNegPatErr (ppr_op op,op_fix))
+ checkErr inf_ok (precParseErr infol infor)
checkPrec op pat right
- = returnRn ()
+ = returnM ()
-- Check precedence of (arg op) or (op arg) respectively
--- If arg is itself an operator application, its precedence should
--- be higher than that of op
-checkSectionPrec left_or_right section op arg
- = case arg of
+-- If arg is itself an operator application, then either
+-- (a) its precedence must be higher than that of op
+-- (b) its precedency & associativity must be the same as that of op
+checkSectionPrec :: FixityDirection -> HsExpr RdrName
+ -> LHsExpr Name -> LHsExpr Name -> RnM ()
+checkSectionPrec direction section op arg
+ = case unLoc arg of
OpApp _ op fix _ -> go_for_it (ppr_op op) fix
- NegApp _ op -> go_for_it pp_prefix_minus negateFixity
- other -> returnRn ()
+ NegApp _ _ -> go_for_it pp_prefix_minus negateFixity
+ other -> returnM ()
where
- HsVar op_name = op
- go_for_it pp_arg_op arg_fix@(Fixity arg_prec _)
- = lookupFixity op_name `thenRn` \ op_fix@(Fixity op_prec _) ->
- checkRn (op_prec < arg_prec)
- (sectionPrecErr (ppr_op op_name, op_fix) (pp_arg_op, arg_fix) section)
+ L _ (HsVar op_name) = op
+ go_for_it pp_arg_op arg_fix@(Fixity arg_prec assoc)
+ = lookupFixityRn op_name `thenM` \ op_fix@(Fixity op_prec _) ->
+ checkErr (op_prec < arg_prec
+ || op_prec == arg_prec && direction == assoc)
+ (sectionPrecErr (ppr_op op_name, op_fix)
+ (pp_arg_op, arg_fix) section)
\end{code}
-Consider
-\begin{verbatim}
- a `op1` b `op2` c
-\end{verbatim}
-@(compareFixity op1 op2)@ tells which way to arrange appication, or
-whether there's an error.
-
-\begin{code}
-compareFixity :: Fixity -> Fixity
- -> (Bool, -- Error please
- Bool) -- Associate to the right: a op1 (b op2 c)
-compareFixity (Fixity prec1 dir1) (Fixity prec2 dir2)
- = case prec1 `compare` prec2 of
- GT -> left
- LT -> right
- EQ -> case (dir1, dir2) of
- (InfixR, InfixR) -> right
- (InfixL, InfixL) -> left
- _ -> error_please
- where
- right = (False, True)
- left = (False, False)
- error_please = (True, False)
-\end{code}
-
-%************************************************************************
-%* *
-\subsubsection{Literals}
-%* *
-%************************************************************************
-
-When literals occur we have to make sure
-that the types and classes they involve
-are made available.
-
-\begin{code}
-litOccurrence (HsChar _)
- = returnRn (unitFV charTyCon_name)
-
-litOccurrence (HsCharPrim _)
- = returnRn (unitFV (getName charPrimTyCon))
-
-litOccurrence (HsString _)
- = returnRn (unitFV listTyCon_name `plusFV` unitFV charTyCon_name)
-
-litOccurrence (HsStringPrim _)
- = returnRn (unitFV (getName addrPrimTyCon))
-
-litOccurrence (HsInt _)
- = lookupImplicitOccRn numClass_RDR `thenRn` \ num ->
- returnRn (unitFV num) -- Int and Integer are forced in by Num
-
-litOccurrence (HsFrac _)
- = lookupImplicitOccRn fractionalClass_RDR `thenRn` \ frac ->
- lookupImplicitOccRn ratioDataCon_RDR `thenRn` \ ratio ->
- returnRn (unitFV frac `plusFV` unitFV ratio)
- -- We have to make sure that the Ratio type is imported with
- -- its constructor, because literals of type Ratio t are
- -- built with that constructor.
- -- The Rational type is needed too, but that will come in
- -- when fractionalClass does.
-
-litOccurrence (HsIntPrim _)
- = returnRn (unitFV (getName intPrimTyCon))
-
-litOccurrence (HsFloatPrim _)
- = returnRn (unitFV (getName floatPrimTyCon))
-
-litOccurrence (HsDoublePrim _)
- = returnRn (unitFV (getName doublePrimTyCon))
-
-litOccurrence (HsLitLit _)
- = lookupImplicitOccRn ccallableClass_RDR `thenRn` \ cc ->
- returnRn (unitFV cc)
-\end{code}
%************************************************************************
%* *
%************************************************************************
\begin{code}
-mkAssertExpr :: RnMS (RenamedHsExpr, FreeVars)
-mkAssertExpr =
- mkImportedGlobalFromRdrName assertErr_RDR `thenRn` \ name ->
- getSrcLocRn `thenRn` \ sloc ->
-
- -- if we're ignoring asserts, return (\ _ e -> e)
- -- if not, return (assertError "src-loc")
-
- if opt_IgnoreAsserts then
- getUniqRn `thenRn` \ uniq ->
+mkAssertErrorExpr :: RnM (HsExpr Name, FreeVars)
+-- Return an expression for (assertError "Foo.hs:27")
+mkAssertErrorExpr
+ = getSrcSpanM `thenM` \ sloc ->
let
- vname = mkSysLocalName uniq SLIT("v")
- expr = HsLam ignorePredMatch
- loc = nameSrcLoc vname
- ignorePredMatch = Match [] [WildPatIn, VarPatIn vname] Nothing
- (GRHSs [GRHS [ExprStmt (HsVar vname) loc] loc]
- EmptyBinds Nothing)
+ expr = HsApp (L sloc (HsVar assertErrorName)) (L sloc (HsLit msg))
+ msg = HsStringPrim (mkFastString (stringToUtf8 (showSDoc (ppr sloc))))
in
- returnRn (expr, unitFV name)
- else
- let
- expr =
- HsApp (HsVar name)
- (HsLit (HsString (_PK_ (showSDoc (ppr sloc)))))
-
- in
- returnRn (expr, unitFV name)
-
+ returnM (expr, emptyFVs)
\end{code}
%************************************************************************
\begin{code}
ppr_op op = quotes (ppr op) -- Here, op can be a Name or a (Var n), where n is a Name
-ppr_opfix (pp_op, fixity) = pp_op <+> brackets (ppr fixity)
pp_prefix_minus = ptext SLIT("prefix `-'")
-dupFieldErr str (dup:rest)
- = hsep [ptext SLIT("duplicate field name"),
- quotes (ppr dup),
- ptext SLIT("in record"), text str]
-
-negPatErr pat
- = sep [pp_prefix_minus <+> ptext SLIT("not applied to literal in pattern"),
- quotes (ppr pat)]
-
-precParseNegPatErr op
- = hang (ptext SLIT("precedence parsing error"))
- 4 (hsep [pp_prefix_minus <+> ptext SLIT("has lower precedence than"),
- ppr_opfix op,
- ptext SLIT("in pattern")])
-
-precParseErr op1 op2
- = hang (ptext SLIT("precedence parsing error"))
- 4 (hsep [ptext SLIT("cannot mix"), ppr_opfix op1, ptext SLIT("and"),
- ppr_opfix op2,
- ptext SLIT("in the same infix expression")])
-
-sectionPrecErr op arg_op section
- = vcat [ptext SLIT("The operator") <+> ppr_opfix op <+> ptext SLIT("of a section"),
- nest 4 (ptext SLIT("must have lower precedence than the operand") <+> ppr_opfix arg_op),
- nest 4 (ptext SLIT("In the section:") <+> quotes (ppr section))]
-
nonStdGuardErr guard
= hang (ptext
SLIT("accepting non-standard pattern guards (-fglasgow-exts to suppress this message)")
) 4 (ppr guard)
-patSigErr ty
- = (ptext SLIT("Illegal signature in pattern:") <+> ppr ty)
- $$ nest 4 (ptext SLIT("Use -fglasgow-exts to permit it"))
-
patSynErr e
= sep [ptext SLIT("Pattern syntax in expression context:"),
nest 4 (ppr e)]
-doStmtListErr e
- = sep [ptext SLIT("`do' statements must end in expression:"),
+doStmtListErr do_or_lc e
+ = sep [quotes (text binder_name) <+> ptext SLIT("statements must end in expression:"),
nest 4 (ppr e)]
+ where
+ binder_name = case do_or_lc of
+ MDoExpr -> "mdo"
+ other -> "do"
+
+#ifdef GHCI
+checkTH e what = returnM () -- OK
+#else
+checkTH e what -- Raise an error in a stage-1 compiler
+ = addErr (vcat [ptext SLIT("Template Haskell") <+> text what <+>
+ ptext SLIT("illegal in a stage-1 compiler"),
+ nest 2 (ppr e)])
+#endif
+
+parStmtErr = addErr (ptext SLIT("Illegal parallel list comprehension: use -fglasgow-exts"))
+
+badIpBinds binds
+ = hang (ptext SLIT("Implicit-parameter bindings illegal in a parallel list comprehension:")) 4
+ (ppr binds)
\end{code}
projects / ghc-hetmet.git / blobdiff