%
-% (c) The GRASP/AQUA Project, Glasgow University, 1992-1996
+% (c) The GRASP/AQUA Project, Glasgow University, 1992-1998
%
\section[RnExpr]{Renaming of expressions}
Basically dependency analysis.
-Handles @Match@, @GRHSsAndBinds@, @HsExpr@, and @Qualifier@ datatypes. In
+Handles @Match@, @GRHSs@, @HsExpr@, and @Qualifier@ datatypes. In
general, all of these functions return a renamed thing, and a set of
free variables.
\begin{code}
-#include "HsVersions.h"
-
module RnExpr (
- rnMatch, rnGRHSsAndBinds, rnPat,
+ rnMatch, rnGRHSs, rnExpr, rnExprs, rnStmts,
checkPrecMatch
) where
-IMP_Ubiq()
-#if defined(__GLASGOW_HASKELL__) && __GLASGOW_HASKELL__ <= 201
-IMPORT_DELOOPER(RnLoop) -- break the RnPass/RnExpr/RnBinds loops
-#else
-import {-# SOURCE #-} RnBinds
-import {-# SOURCE #-} RnSource ( rnHsSigType )
-#endif
+#include "HsVersions.h"
+
+import {-# SOURCE #-} RnSource ( rnSrcDecls, rnBindsAndThen, rnBinds )
+
+-- 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 CmdLineOpts ( opt_GlasgowExts )
-import BasicTypes ( Fixity(..), FixityDirection(..) )
-import PrelInfo ( numClass_RDR, fractionalClass_RDR, eqClass_RDR, ccallableClass_RDR,
- creturnableClass_RDR, monadZeroClass_RDR, enumClass_RDR, ordClass_RDR,
- ratioDataCon_RDR, negate_RDR
- )
-import TysPrim ( charPrimTyCon, addrPrimTyCon, intPrimTyCon,
- floatPrimTyCon, doublePrimTyCon
- )
-import TyCon ( TyCon )
-import Id ( GenId )
-import ErrUtils ( addErrLoc, addShortErrLocLine )
-import Name
-import Pretty
-import UniqFM ( lookupUFM{-, ufmToList ToDo:rm-} )
-import UniqSet ( emptyUniqSet, unitUniqSet,
- unionUniqSets, unionManyUniqSets,
- SYN_IE(UniqSet)
- )
-import Util ( Ord3(..), removeDups, panic, pprPanic, assertPanic )
+import RnNames ( importsFromLocalDecls )
+import RnTypes ( rnHsTypeFVs, rnPat, litFVs, rnOverLit, rnPatsAndThen,
+ dupFieldErr, precParseErr, sectionPrecErr, patSigErr, checkTupSize )
+import CmdLineOpts ( DynFlag(..), opt_IgnoreAsserts )
+import BasicTypes ( Fixity(..), FixityDirection(..), IPName(..),
+ defaultFixity, negateFixity, compareFixity )
+import PrelNames ( hasKey, assertIdKey,
+ foldrName, buildName,
+ cCallableClassName, cReturnableClassName,
+ enumClassName,
+ splitName, fstName, sndName, ioDataConName,
+ replicatePName, mapPName, filterPName,
+ crossPName, zipPName, toPName,
+ enumFromToPName, enumFromThenToPName, assertErrorName,
+ negateName, monadNames, mfixName )
+import Name ( Name, nameOccName )
+import NameSet
+import UnicodeUtil ( stringToUtf8 )
+import UniqFM ( isNullUFM )
+import UniqSet ( emptyUniqSet )
+import Util ( isSingleton )
+import List ( intersectBy, unzip4 )
+import ListSetOps ( removeDups )
import Outputable
-
+import FastString
\end{code}
-*********************************************************
-* *
-\subsection{Patterns}
-* *
-*********************************************************
-
-\begin{code}
-rnPat :: RdrNamePat -> RnMS s RenamedPat
-
-rnPat WildPatIn = returnRn WildPatIn
-
-rnPat (VarPatIn name)
- = lookupBndrRn name `thenRn` \ vname ->
- returnRn (VarPatIn vname)
-
-rnPat (LitPatIn lit)
- = litOccurrence lit `thenRn_`
- lookupImplicitOccRn eqClass_RDR `thenRn_` -- Needed to find equality on pattern
- returnRn (LitPatIn lit)
-
-rnPat (LazyPatIn pat)
- = rnPat pat `thenRn` \ pat' ->
- returnRn (LazyPatIn pat')
-
-rnPat (AsPatIn name pat)
- = rnPat pat `thenRn` \ pat' ->
- lookupBndrRn name `thenRn` \ vname ->
- returnRn (AsPatIn vname pat')
-
-rnPat (ConPatIn con pats)
- = lookupOccRn con `thenRn` \ con' ->
- mapRn rnPat pats `thenRn` \ patslist ->
- returnRn (ConPatIn con' patslist)
-
-rnPat (ConOpPatIn pat1 con _ pat2)
- = rnPat pat1 `thenRn` \ pat1' ->
- lookupOccRn con `thenRn` \ con' ->
- lookupFixity con `thenRn` \ fixity ->
- rnPat pat2 `thenRn` \ pat2' ->
- mkConOpPatRn pat1' con' fixity pat2'
-
--- 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' ->
- returnRn (NegPatIn pat')
- where
- valid_neg_pat (LitPatIn (HsInt _)) = True
- valid_neg_pat (LitPatIn (HsFrac _)) = True
- valid_neg_pat _ = False
-
-rnPat (ParPatIn pat)
- = rnPat pat `thenRn` \ pat' ->
- returnRn (ParPatIn pat')
-
-rnPat (NPlusKPatIn name lit)
- = litOccurrence lit `thenRn_`
- lookupImplicitOccRn ordClass_RDR `thenRn_`
- lookupBndrRn name `thenRn` \ name' ->
- returnRn (NPlusKPatIn name' lit)
-
-rnPat (ListPatIn pats)
- = addImplicitOccRn listType_name `thenRn_`
- mapRn rnPat pats `thenRn` \ patslist ->
- returnRn (ListPatIn patslist)
-
-rnPat (TuplePatIn pats)
- = addImplicitOccRn (tupleType_name (length pats)) `thenRn_`
- mapRn rnPat pats `thenRn` \ patslist ->
- returnRn (TuplePatIn patslist)
-
-rnPat (RecPatIn con rpats)
- = lookupOccRn con `thenRn` \ con' ->
- rnRpats rpats `thenRn` \ rpats' ->
- returnRn (RecPatIn con' rpats')
-\end{code}
-
************************************************************************
* *
\subsection{Match}
************************************************************************
\begin{code}
-rnMatch, rnMatch1 :: RdrNameMatch -> RnMS s (RenamedMatch, FreeVars)
-
--- The only tricky bit here is that we want to do a single
--- bindLocalsRn for all the matches together, so that we spot
--- the repeated variable in
--- f x x = 1
-
-rnMatch match
- = bindLocalsRn "pattern" (get_binders match) $ \ new_binders ->
- rnMatch1 match `thenRn` \ (match', fvs) ->
- returnRn (match', fvs `minusNameSet` mkNameSet new_binders)
- where
- get_binders (GRHSMatch _) = []
- get_binders (PatMatch pat match) = collectPatBinders pat ++ get_binders match
-
-rnMatch1 (PatMatch pat match)
- = rnPat pat `thenRn` \ pat' ->
- rnMatch1 match `thenRn` \ (match', fvs) ->
- returnRn (PatMatch pat' match', fvs)
-
-rnMatch1 (GRHSMatch grhss_and_binds)
- = rnGRHSsAndBinds grhss_and_binds `thenRn` \ (grhss_and_binds', fvs) ->
- returnRn (GRHSMatch grhss_and_binds', fvs)
+rnMatch :: HsMatchContext Name -> RdrNameMatch -> RnM (RenamedMatch, FreeVars)
+
+rnMatch ctxt match@(Match pats maybe_rhs_sig grhss)
+ = addSrcLoc (getMatchLoc match) $
+
+ -- Deal with the rhs type signature
+ bindPatSigTyVars rhs_sig_tys $
+ doptM Opt_GlasgowExts `thenM` \ opt_GlasgowExts ->
+ (case maybe_rhs_sig of
+ Nothing -> returnM (Nothing, emptyFVs)
+ Just ty | opt_GlasgowExts -> rnHsTypeFVs doc_sig ty `thenM` \ (ty', ty_fvs) ->
+ returnM (Just ty', ty_fvs)
+ | otherwise -> addErr (patSigErr ty) `thenM_`
+ returnM (Nothing, emptyFVs)
+ ) `thenM` \ (maybe_rhs_sig', ty_fvs) ->
+
+ -- Now the main event
+ rnPatsAndThen ctxt pats $ \ pats' ->
+ rnGRHSs ctxt grhss `thenM` \ (grhss', grhss_fvs) ->
+
+ returnM (Match pats' maybe_rhs_sig' grhss', grhss_fvs `plusFV` ty_fvs)
+ -- The bindPatSigTyVars 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 (GRHSsAndBinds)}
+\subsubsection{Guarded right-hand sides (GRHSs)}
%* *
%************************************************************************
\begin{code}
-rnGRHSsAndBinds :: RdrNameGRHSsAndBinds -> RnMS s (RenamedGRHSsAndBinds, FreeVars)
+rnGRHSs :: HsMatchContext Name -> RdrNameGRHSs -> RnM (RenamedGRHSs, FreeVars)
-rnGRHSsAndBinds (GRHSsAndBindsIn grhss binds)
- = rnBinds binds $ \ binds' ->
- rnGRHSs grhss `thenRn` \ (grhss', fvGRHS) ->
- returnRn (GRHSsAndBindsIn grhss' binds', fvGRHS)
- where
- rnGRHSs [] = returnRn ([], emptyNameSet)
-
- rnGRHSs (grhs:grhss)
- = rnGRHS grhs `thenRn` \ (grhs', fvs) ->
- rnGRHSs grhss `thenRn` \ (grhss', fvss) ->
- returnRn (grhs' : grhss', fvs `unionNameSets` fvss)
-
- rnGRHS (GRHS guard expr locn)
- = pushSrcLocRn locn $
- (if not (opt_GlasgowExts || is_standard_guard guard) then
- addWarnRn (nonStdGuardErr guard)
- else
- returnRn ()
- ) `thenRn_`
-
- (rnStmts rnExpr guard $ \ guard' ->
- -- This nested thing deals with scope and
- -- the free vars of the guard, and knocking off the
- -- free vars of the rhs that are bound by the guard
-
- rnExpr expr `thenRn` \ (expr', fvse) ->
- returnRn (GRHS guard' expr' locn, fvse))
-
- rnGRHS (OtherwiseGRHS expr locn)
- = pushSrcLocRn locn $
- rnExpr expr `thenRn` \ (expr', fvs) ->
- returnRn (GRHS [] expr' locn, fvs)
+rnGRHSs ctxt (GRHSs grhss binds _)
+ = rnBindsAndThen binds $ \ binds' ->
+ mapFvRn (rnGRHS ctxt) grhss `thenM` \ (grhss', fvGRHSs) ->
+ returnM (GRHSs grhss' binds' placeHolderType, fvGRHSs)
+
+rnGRHS ctxt (GRHS guarded locn)
+ = addSrcLoc locn $
+ 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' locn, 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 [GuardStmt _ _] = True
- is_standard_guard other = False
+ is_standard_guard [ResultStmt _ _] = True
+ is_standard_guard [ExprStmt _ _ _, ResultStmt _ _] = True
+ is_standard_guard other = False
\end{code}
%************************************************************************
%************************************************************************
\begin{code}
-rnExprs :: [RdrNameHsExpr] -> RnMS s ([RenamedHsExpr], FreeVars)
-rnExprs ls =
- rnExprs' ls [] `thenRn` \ (exprs, fvExprs) ->
- returnRn (exprs, unionManyNameSets fvExprs)
-
-rnExprs' [] acc = returnRn ([], acc)
-rnExprs' (expr:exprs) acc
- = rnExpr expr `thenRn` \ (expr', fvExpr) ->
- rnExprs' exprs (fvExpr:acc) `thenRn` \ (exprs', fvExprs) ->
- returnRn (expr':exprs', fvExprs)
+rnExprs :: [RdrNameHsExpr] -> RnM ([RenamedHsExpr], FreeVars)
+rnExprs ls = rnExprs' ls emptyUniqSet
+ where
+ rnExprs' [] acc = returnM ([], acc)
+ rnExprs' (expr:exprs) acc
+ = rnExpr 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' `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
+ | otherwise = result
\end{code}
-Variables. We look up the variable and return the resulting name. The
-interesting question is what the free-variable set should be. We
-don't want to return imported or prelude things as free vars. So we
-look at the Name returned from the lookup, and make it part of the
-free-var set iff if it's a LocallyDefined Name.
-\end{itemize}
+Variables. We look up the variable and return the resulting name.
\begin{code}
-rnExpr :: RdrNameHsExpr -> RnMS s (RenamedHsExpr, FreeVars)
+rnExpr :: RdrNameHsExpr -> RnM (RenamedHsExpr, FreeVars)
rnExpr (HsVar v)
- = lookupOccRn v `thenRn` \ vname ->
- returnRn (HsVar vname, if isLocallyDefined vname
- then unitNameSet vname
- else emptyUniqSet)
+ = lookupOccRn v `thenM` \ name ->
+ if name `hasKey` assertIdKey && not opt_IgnoreAsserts then
+ -- We expand it to (GHC.Err.assertError location_string)
+ mkAssertErrorExpr
+ else
+ -- 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)
+ = newIPName v `thenM` \ name ->
+ let
+ fvs = case name of
+ Linear _ -> mkFVs [splitName, fstName, sndName]
+ Dupable _ -> emptyFVs
+ in
+ returnM (HsIPVar name, fvs)
rnExpr (HsLit lit)
- = litOccurrence lit `thenRn_`
- returnRn (HsLit lit, emptyNameSet)
+ = litFVs lit `thenM` \ fvs ->
+ returnM (HsLit lit, fvs)
+
+rnExpr (HsOverLit lit)
+ = rnOverLit lit `thenM` \ (lit', fvs) ->
+ returnM (HsOverLit lit', fvs)
rnExpr (HsLam match)
- = rnMatch match `thenRn` \ (match', fvMatch) ->
- returnRn (HsLam match', fvMatch)
+ = rnMatch LambdaExpr match `thenM` \ (match', fvMatch) ->
+ returnM (HsLam match', fvMatch)
rnExpr (HsApp fun arg)
- = rnExpr fun `thenRn` \ (fun',fvFun) ->
- rnExpr arg `thenRn` \ (arg',fvArg) ->
- returnRn (HsApp fun' arg', fvFun `unionNameSets` fvArg)
+ = rnExpr fun `thenM` \ (fun',fvFun) ->
+ rnExpr arg `thenM` \ (arg',fvArg) ->
+ returnM (HsApp fun' arg', fvFun `plusFV` fvArg)
-rnExpr (OpApp e1 op@(HsVar op_name) _ e2)
- = rnExpr e1 `thenRn` \ (e1', fv_e1) ->
- rnExpr e2 `thenRn` \ (e2', fv_e2) ->
- rnExpr op `thenRn` \ (op', fv_op) ->
+rnExpr (OpApp e1 op _ e2)
+ = rnExpr e1 `thenM` \ (e1', fv_e1) ->
+ rnExpr e2 `thenM` \ (e2', fv_e2) ->
+ rnExpr op `thenM` \ (op'@(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
- lookupFixity op_name `thenRn` \ fixity ->
- getModeRn `thenRn` \ mode ->
- (case mode of
- SourceMode -> mkOpAppRn e1' op' fixity e2'
- InterfaceMode _ -> returnRn (OpApp e1' op' fixity e2')
- ) `thenRn` \ final_e ->
-
- returnRn (final_e,
- fv_e1 `unionNameSets` fv_op `unionNameSets` 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)
+ -- Don't even look up the fixity when in interface mode
+ getModeRn `thenM` \ mode ->
+ (if isInterfaceMode mode
+ then returnM (OpApp e1' op' defaultFixity e2')
+ else lookupFixityRn op_name `thenM` \ fixity ->
+ mkOpAppRn e1' op' fixity e2'
+ ) `thenM` \ final_e ->
+
+ returnM (final_e,
+ fv_e1 `plusFV` fv_op `plusFV` fv_e2)
+
+rnExpr (NegApp e _)
+ = rnExpr 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)
-
-rnExpr (SectionL expr op)
- = rnExpr expr `thenRn` \ (expr', fvs_expr) ->
- rnExpr op `thenRn` \ (op', fvs_op) ->
- returnRn (SectionL expr' op', fvs_op `unionNameSets` fvs_expr)
-
-rnExpr (SectionR op expr)
- = rnExpr op `thenRn` \ (op', fvs_op) ->
- rnExpr expr `thenRn` \ (expr', fvs_expr) ->
- returnRn (SectionR op' expr', fvs_op `unionNameSets` fvs_expr)
-
-rnExpr (CCall fun args may_gc is_casm fake_result_ty)
- = lookupImplicitOccRn ccallableClass_RDR `thenRn_`
- lookupImplicitOccRn creturnableClass_RDR `thenRn_`
- rnExprs args `thenRn` \ (args', fvs_args) ->
- returnRn (CCall fun args' may_gc is_casm fake_result_ty, fvs_args)
-
-rnExpr (HsSCC label expr)
- = rnExpr expr `thenRn` \ (expr', fvs_expr) ->
- returnRn (HsSCC label expr', fvs_expr)
+ = rnExpr 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 loc)
+ = addSrcLoc loc $
+ checkTH e "bracket" `thenM_`
+ rnBracket br_body `thenM` \ (body', fvs_e) ->
+ returnM (HsBracket body' loc, fvs_e `plusFV` thProxyName)
+
+rnExpr e@(HsSplice n splice loc)
+ = addSrcLoc loc $
+ checkTH e "splice" `thenM_`
+ newLocalsRn [(n,loc)] `thenM` \ [n'] ->
+ rnExpr splice `thenM` \ (splice', fvs_e) ->
+ returnM (HsSplice n' splice' loc, fvs_e `plusFV` thProxyName)
+
+rnExpr e@(HsReify (Reify flavour name))
+ = checkTH e "reify" `thenM_`
+ lookupGlobalOccRn name `thenM` \ name' ->
+ -- For now, we can only reify top-level things
+ returnM (HsReify (Reify flavour name'), unitFV name' `plusFV` thProxyName)
+
+rnExpr section@(SectionL expr op)
+ = rnExpr expr `thenM` \ (expr', fvs_expr) ->
+ rnExpr 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 `thenM` \ (op', fvs_op) ->
+ rnExpr expr `thenM` \ (expr', fvs_expr) ->
+ checkSectionPrec InfixR section op' expr' `thenM_`
+ returnM (SectionR op' expr', fvs_op `plusFV` fvs_expr)
+
+rnExpr (HsCCall fun args may_gc is_casm _)
+ -- Check out the comment on RnIfaces.getNonWiredDataDecl about ccalls
+ = rnExprs args `thenM` \ (args', fvs_args) ->
+ returnM (HsCCall fun args' may_gc is_casm placeHolderType,
+ fvs_args `plusFV` mkFVs [cCallableClassName,
+ cReturnableClassName,
+ ioDataConName])
+
+rnExpr (HsSCC lbl expr)
+ = rnExpr 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) ->
- mapAndUnzipRn rnMatch ms `thenRn` \ (new_ms, ms_fvs) ->
- returnRn (HsCase new_expr new_ms src_loc, unionManyNameSets (e_fvs : ms_fvs))
+ = addSrcLoc src_loc $
+ rnExpr expr `thenM` \ (new_expr, e_fvs) ->
+ mapFvRn (rnMatch CaseAlt) ms `thenM` \ (new_ms, ms_fvs) ->
+ returnM (HsCase new_expr new_ms src_loc, e_fvs `plusFV` ms_fvs)
rnExpr (HsLet binds expr)
- = rnBinds binds $ \ binds' ->
- rnExpr expr `thenRn` \ (expr',fvExpr) ->
- returnRn (HsLet binds' expr', fvExpr)
-
-rnExpr (HsDo do_or_lc stmts src_loc)
- = pushSrcLocRn src_loc $
- lookupImplicitOccRn monadZeroClass_RDR `thenRn_` -- Forces Monad to come too
- (rnStmts rnExpr stmts $ \ stmts' ->
- returnRn (HsDo do_or_lc stmts' src_loc, emptyNameSet))
-
-rnExpr (ExplicitList exps)
- = addImplicitOccRn listType_name `thenRn_`
- rnExprs exps `thenRn` \ (exps', fvs) ->
- returnRn (ExplicitList exps', fvs)
-
-rnExpr (ExplicitTuple exps)
- = addImplicitOccRn (tupleType_name (length exps)) `thenRn_`
- rnExprs exps `thenRn` \ (exps', fvExps) ->
- returnRn (ExplicitTuple exps', fvExps)
-
-rnExpr (RecordCon (HsVar con) rbinds)
- = lookupOccRn con `thenRn` \ conname ->
- rnRbinds "construction" rbinds `thenRn` \ (rbinds', fvRbinds) ->
- returnRn (RecordCon (HsVar conname) rbinds', fvRbinds)
+ = rnBindsAndThen binds $ \ binds' ->
+ rnExpr expr `thenM` \ (expr',fvExpr) ->
+ returnM (HsLet binds' expr', fvExpr)
+
+rnExpr e@(HsDo do_or_lc stmts _ _ src_loc)
+ = addSrcLoc src_loc $
+ rnStmts do_or_lc stmts `thenM` \ (stmts', fvs) ->
+
+ -- Check the statement list ends in an expression
+ case last stmts' of {
+ ResultStmt _ _ -> returnM () ;
+ _ -> addErr (doStmtListErr do_or_lc e)
+ } `thenM_`
+
+ -- Generate the rebindable syntax for the monad
+ mapAndUnzipM lookupSyntaxName
+ (syntax_names do_or_lc) `thenM` \ (monad_names', monad_fvs) ->
+
+ returnM (HsDo do_or_lc stmts' monad_names' placeHolderType src_loc,
+ fvs `plusFV` implicit_fvs do_or_lc `plusFV` plusFVs monad_fvs)
+ where
+ implicit_fvs PArrComp = mkFVs [replicatePName, mapPName, filterPName, crossPName, zipPName]
+ implicit_fvs ListComp = mkFVs [foldrName, buildName]
+ implicit_fvs DoExpr = emptyFVs
+ implicit_fvs MDoExpr = emptyFVs
+
+ syntax_names DoExpr = monadNames
+ syntax_names MDoExpr = monadNames ++ [mfixName]
+ syntax_names 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 `addOneFV` toPName `addOneFV` parrTyCon_name)
+
+rnExpr e@(ExplicitTuple exps boxity)
+ = checkTupSize tup_size `thenM_`
+ rnExprs exps `thenM` \ (exps', fvs) ->
+ returnM (ExplicitTuple exps' boxity, fvs `addOneFV` tycon_name)
+ where
+ tup_size = length exps
+ tycon_name = tupleTyCon_name boxity tup_size
+
+rnExpr (RecordCon con_id rbinds)
+ = lookupOccRn con_id `thenM` \ conname ->
+ rnRbinds "construction" rbinds `thenM` \ (rbinds', fvRbinds) ->
+ returnM (RecordCon conname rbinds', fvRbinds `addOneFV` conname)
rnExpr (RecordUpd expr rbinds)
- = rnExpr expr `thenRn` \ (expr', fvExpr) ->
- rnRbinds "update" rbinds `thenRn` \ (rbinds', fvRbinds) ->
- returnRn (RecordUpd expr' rbinds', fvExpr `unionNameSets` fvRbinds)
+ = rnExpr 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 (\ sty -> text "an expression") pty `thenRn` \ pty' ->
- returnRn (ExprWithTySig expr' pty', fvExpr)
+ = rnExpr 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 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, unionManyNameSets [fvP, fvB1, fvB2])
+ = addSrcLoc src_loc $
+ rnExpr p `thenM` \ (p', fvP) ->
+ rnExpr b1 `thenM` \ (b1', fvB1) ->
+ rnExpr b2 `thenM` \ (b2', fvB2) ->
+ returnM (HsIf p' b1' b2' src_loc, 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_`
- rn_seq seq `thenRn` \ (new_seq, fvs) ->
- returnRn (ArithSeqIn new_seq, fvs)
- 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 `unionNameSets` fvExpr2)
-
- rn_seq (FromTo expr1 expr2)
- = rnExpr expr1 `thenRn` \ (expr1', fvExpr1) ->
- rnExpr expr2 `thenRn` \ (expr2', fvExpr2) ->
- returnRn (FromTo expr1' expr2', fvExpr1 `unionNameSets` 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',
- unionManyNameSets [fvExpr1, fvExpr2, fvExpr3])
+ = rnArithSeq seq `thenM` \ (new_seq, fvs) ->
+ returnM (ArithSeqIn new_seq, fvs `addOneFV` enumClassName)
+
+rnExpr (PArrSeqIn seq)
+ = rnArithSeq seq `thenM` \ (new_seq, fvs) ->
+ returnM (PArrSeqIn new_seq,
+ fvs `plusFV` mkFVs [enumFromToPName, enumFromThenToPName])
+\end{code}
+
+These three are pattern syntax appearing in expressions.
+Since all the symbols are reservedops we can simply reject them.
+We return a (bogus) EWildPat in each case.
+
+\begin{code}
+rnExpr e@EWildPat = addErr (patSynErr e) `thenM_`
+ returnM (EWildPat, emptyFVs)
+
+rnExpr e@(EAsPat _ _) = addErr (patSynErr e) `thenM_`
+ returnM (EWildPat, emptyFVs)
+
+rnExpr e@(ELazyPat _) = addErr (patSynErr e) `thenM_`
+ returnM (EWildPat, emptyFVs)
\end{code}
%************************************************************************
%* *
+ Arithmetic sequences
+%* *
+%************************************************************************
+
+\begin{code}
+rnArithSeq (From expr)
+ = rnExpr expr `thenM` \ (expr', fvExpr) ->
+ returnM (From expr', fvExpr)
+
+rnArithSeq (FromThen expr1 expr2)
+ = rnExpr expr1 `thenM` \ (expr1', fvExpr1) ->
+ rnExpr expr2 `thenM` \ (expr2', fvExpr2) ->
+ returnM (FromThen expr1' expr2', fvExpr1 `plusFV` fvExpr2)
+
+rnArithSeq (FromTo expr1 expr2)
+ = rnExpr expr1 `thenM` \ (expr1', fvExpr1) ->
+ rnExpr expr2 `thenM` \ (expr2', fvExpr2) ->
+ returnM (FromTo expr1' expr2', fvExpr1 `plusFV` fvExpr2)
+
+rnArithSeq (FromThenTo expr1 expr2 expr3)
+ = rnExpr expr1 `thenM` \ (expr1', fvExpr1) ->
+ rnExpr expr2 `thenM` \ (expr2', fvExpr2) ->
+ rnExpr 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
- = mapRn field_dup_err dup_fields `thenRn_`
- mapAndUnzipRn rn_rbind rbinds `thenRn` \ (rbinds', fvRbind_s) ->
- returnRn (rbinds', unionManyNameSets fvRbind_s)
+ = mappM_ field_dup_err dup_fields `thenM_`
+ mapFvRn rn_rbind rbinds `thenM` \ (rbinds', fvRbind) ->
+ returnM (rbinds', fvRbind)
where
- (_, dup_fields) = removeDups cmp [ f | (f,_,_) <- rbinds ]
+ (_, dup_fields) = removeDups compare [ f | (f,_) <- rbinds ]
- field_dup_err dups = addErrRn (dupFieldErr str dups)
+ field_dup_err dups = addErr (dupFieldErr str dups)
- rn_rbind (field, expr, pun)
- = lookupGlobalOccRn field `thenRn` \ fieldname ->
- rnExpr expr `thenRn` \ (expr', fvExpr) ->
- returnRn ((fieldname, expr', pun), fvExpr)
-
-rnRpats rpats
- = mapRn field_dup_err dup_fields `thenRn_`
- mapRn rn_rpat rpats
- where
- (_, dup_fields) = removeDups cmp [ f | (f,_,_) <- rpats ]
+ rn_rbind (field, expr)
+ = lookupGlobalOccRn field `thenM` \ fieldname ->
+ rnExpr expr `thenM` \ (expr', fvExpr) ->
+ returnM ((fieldname, expr'), fvExpr `addOneFV` fieldname)
+\end{code}
- field_dup_err dups = addErrRn (dupFieldErr "pattern" dups)
+%************************************************************************
+%* *
+ Template Haskell brackets
+%* *
+%************************************************************************
- rn_rpat (field, pat, pun)
- = lookupGlobalOccRn field `thenRn` \ fieldname ->
- rnPat pat `thenRn` \ pat' ->
- returnRn (fieldname, pat', pun)
+\begin{code}
+rnBracket (ExpBr e) = rnExpr e `thenM` \ (e', fvs) ->
+ returnM (ExpBr e', fvs)
+rnBracket (PatBr p) = rnPat 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 = rdr_env `plusGlobalRdrEnv` tcg_rdr_env gbl }) $
+
+ rnSrcDecls group `thenM` \ (tcg_env, group', fvs) ->
+ -- Discard the tcg_env; it contains only extra info about fixity
+
+ returnM (DecBr group', fvs)
\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}
-type RnExprTy s = RdrNameHsExpr -> RnMS s (RenamedHsExpr, FreeVars)
+rnStmts :: HsStmtContext Name -> [RdrNameStmt] -> RnM ([RenamedStmt], FreeVars)
+
+rnStmts MDoExpr stmts = rnMDoStmts stmts
+rnStmts ctxt stmts = rnNormalStmts ctxt stmts
+
+rnNormalStmts :: HsStmtContext Name -> [RdrNameStmt] -> RnM ([RenamedStmt], 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 (ExprStmt expr _ src_loc : stmts)
+ = addSrcLoc src_loc $
+ rnExpr expr `thenM` \ (expr', fv_expr) ->
+ rnNormalStmts ctxt stmts `thenM` \ (stmts', fvs) ->
+ returnM (ExprStmt expr' placeHolderType src_loc : stmts',
+ fv_expr `plusFV` fvs)
+
+rnNormalStmts ctxt [ResultStmt expr src_loc]
+ = addSrcLoc src_loc $
+ rnExpr expr `thenM` \ (expr', fv_expr) ->
+ returnM ([ResultStmt expr' src_loc], fv_expr)
+
+rnNormalStmts ctxt (BindStmt pat expr src_loc : stmts)
+ = addSrcLoc src_loc $
+ rnExpr expr `thenM` \ (expr', fv_expr) ->
+ -- The binders do not scope over the expression
+
+ rnPatsAndThen (StmtCtxt ctxt) [pat] $ \ [pat'] ->
+ rnNormalStmts ctxt stmts `thenM` \ (stmts', fvs) ->
+ returnM (BindStmt pat' expr' src_loc : stmts',
+ fv_expr `plusFV` fvs) -- fv_expr shouldn't really be filtered by
+ -- the rnPatsAndThen, but it does not matter
+
+rnNormalStmts ctxt (LetStmt binds : stmts)
+ = checkErr (ok ctxt binds) (badIpBinds binds) `thenM_`
+ rnBindsAndThen binds ( \ binds' ->
+ rnNormalStmts ctxt stmts `thenM` \ (stmts', fvs) ->
+ returnM (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 _) (IPBinds _ _) = False
+ ok _ _ = True
-rnStmts :: RnExprTy s
- -> [RdrNameStmt]
- -> ([RenamedStmt] -> RnMS s (a, FreeVars))
- -> RnMS s (a, FreeVars)
+rnNormalStmts ctxt (ParStmt stmtss : stmts)
+ = mapFvRn (rnNormalStmts (ParStmtCtxt ctxt)) stmtss `thenM` \ (stmtss', fv_stmtss) ->
+ let
+ bndrss = map collectStmtsBinders stmtss'
+ in
+ foldlM checkBndrs [] bndrss `thenM` \ new_binders ->
+ bindLocalNamesFV new_binders $
+ -- 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) ->
+ returnM (ParStmtOut (bndrss `zip` stmtss') : stmts',
+ fv_stmtss `plusFV` fvs)
+
+ where
+ checkBndrs all_bndrs bndrs
+ = checkErr (null common) (err (head common)) `thenM_`
+ returnM (bndrs ++ all_bndrs)
+ where
+ common = intersectBy eqOcc all_bndrs bndrs
-rnStmts rn_expr [] thing_inside
- = thing_inside []
+ eqOcc n1 n2 = nameOccName n1 == nameOccName n2
+ err v = ptext SLIT("Duplicate binding in parallel list comprehension for:")
+ <+> quotes (ppr v)
-rnStmts rn_expr (stmt:stmts) thing_inside
- = rnStmt rn_expr stmt $ \ stmt' ->
- rnStmts rn_expr stmts $ \ stmts' ->
- thing_inside (stmt' : stmts')
+rnNormalStmts ctxt stmts = pprPanic "rnNormalStmts" (ppr stmts)
+\end{code}
-rnStmt :: RnExprTy s -> RdrNameStmt -> (RenamedStmt -> RnMS s (a, FreeVars)) -> RnMS s (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) ->
- bindLocalsRn "pattern in do binding" binders $ \ new_binders ->
- rnPat pat `thenRn` \ pat' ->
+%************************************************************************
+%* *
+\subsubsection{Precedence Parsing}
+%* *
+%************************************************************************
- thing_inside (BindStmt pat' expr' src_loc) `thenRn` \ (result, fvs) ->
- returnRn (result, fv_expr `unionNameSets` (fvs `minusNameSet` mkNameSet new_binders))
+\begin{code}
+type Defs = NameSet
+type Uses = NameSet -- Same as FreeVars really
+type FwdRefs = NameSet
+type Segment = (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
+ [RenamedStmt])
+
+----------------------------------------------------
+rnMDoStmts :: [RdrNameStmt] -> RnM ([RenamedStmt], FreeVars)
+rnMDoStmts stmts
+ = -- Step1: bring all the binders of the mdo into scope
+ bindLocalsRn 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
+ mappM rn_mdo_stmt 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
- binders = collectPatBinders pat
-
-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 `unionNameSets` 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 `unionNameSets` 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 `unionNameSets` fvs)
-
-rnStmt rn_expr (LetStmt binds) thing_inside
- = rnBinds binds $ \ binds' ->
- thing_inside (LetStmt binds')
+ doc = text "In a mdo-expression"
+
+----------------------------------------------------
+rn_mdo_stmt :: RdrNameStmt -> RnM Segment
+ -- Assumes all binders are already in scope
+ -- Turns each stmt into a singleton Stmt
+
+rn_mdo_stmt (ExprStmt expr _ src_loc)
+ = addSrcLoc src_loc (rnExpr expr) `thenM` \ (expr', fvs) ->
+ returnM (emptyNameSet, fvs, emptyNameSet,
+ [ExprStmt expr' placeHolderType src_loc])
+
+rn_mdo_stmt (ResultStmt expr src_loc)
+ = addSrcLoc src_loc (rnExpr expr) `thenM` \ (expr', fvs) ->
+ returnM (emptyNameSet, fvs, emptyNameSet,
+ [ResultStmt expr' src_loc])
+
+rn_mdo_stmt (BindStmt pat expr src_loc)
+ = addSrcLoc src_loc $
+ rnExpr expr `thenM` \ (expr', fv_expr) ->
+ rnPat pat `thenM` \ (pat', fv_pat) ->
+ let
+ bndrs = mkNameSet (collectPatBinders pat')
+ fvs = fv_expr `plusFV` fv_pat
+ in
+ returnM (bndrs, fvs, bndrs `intersectNameSet` fvs,
+ [BindStmt pat' expr' src_loc])
+
+rn_mdo_stmt (LetStmt binds)
+ = rnBinds binds `thenM` \ (binds', fv_binds) ->
+ returnM (mkNameSet (collectHsBinders binds'),
+ fv_binds, emptyNameSet, [LetStmt binds'])
+
+rn_mdo_stmt stmt@(ParStmt _) -- Syntactically illegal in mdo
+ = pprPanic "rn_mdo_stmt" (ppr stmt)
+
+
+addFwdRefs :: [Segment] -> [Segment]
+-- 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
+ mk_seg (defs, uses, fwds, stmts) (segs, seg_defs)
+ = (new_seg : segs, all_defs)
+ where
+ new_seg = (defs, uses, new_fwds, stmts)
+ all_defs = seg_defs `unionNameSets` defs
+ new_fwds = fwds `unionNameSets` (uses `intersectNameSet` seg_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] -> [Segment]
+
+glomSegments [seg] = [seg]
+glomSegments ((defs,uses,fwds,stmts) : 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 = stmts ++ concat ss
+
+ grab :: NameSet -- The client
+ -> [Segment]
+ -> ([Segment], -- Needed by the 'client'
+ [Segment]) -- 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] -> ([RenamedStmt], FreeVars)
+
+segsToStmts [] = ([], emptyFVs)
+segsToStmts ((defs, uses, fwds, ss) : segs)
+ = (new_stmt : later_stmts, later_uses `plusFV` uses)
+ where
+ (later_stmts, later_uses) = segsToStmts segs
+ new_stmt | non_rec = head ss
+ | otherwise = RecStmt rec_names ss []
+ where
+ non_rec = isSingleton ss && isEmptyNameSet fwds
+ rec_names = nameSetToList (fwds `plusFV` (defs `intersectNameSet` later_uses))
+ -- The names for the fixpoint are
+ -- (a) the ones needed after the RecStmt
+ -- (b) the forward refs within the fixpoint
\end{code}
%************************************************************************
Furthermore, the second argument is guaranteed not to be another
operator application. Why? Because the parser parses all
-operator appications left-associatively.
+operator appications left-associatively, EXCEPT negation, which
+we need to handle specially.
\begin{code}
-mkOpAppRn :: RenamedHsExpr -> RenamedHsExpr -> Fixity -> RenamedHsExpr
- -> RnMS s RenamedHsExpr
-
-mkOpAppRn e1@(OpApp e11 op1 fix1 e12)
- op2 fix2 e2
+mkOpAppRn :: RenamedHsExpr -- Left operand; already rearranged
+ -> RenamedHsExpr -> Fixity -- Operator and fixity
+ -> RenamedHsExpr -- Right operand (not an OpApp, but might
+ -- be a NegApp)
+ -> RnM RenamedHsExpr
+
+---------------------------
+-- (e11 `op1` e12) `op2` e2
+mkOpAppRn e1@(OpApp e11 op1 fix1 e12) op2 fix2 e2
| nofix_error
- = addErrRn (precParseErr (get op1,fix1) (get 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)
- | rearrange_me
- = mkOpAppRn e12 op2 fix2 e2 `thenRn` \ new_e ->
- returnRn (OpApp e11 op1 fix1 new_e)
+ | associate_right
+ = mkOpAppRn e12 op2 fix2 e2 `thenM` \ new_e ->
+ returnM (OpApp e11 op1 fix1 new_e)
where
- (nofix_error, rearrange_me) = compareFixity fix1 fix2
+ (nofix_error, associate_right) = compareFixity fix1 fix2
-mkOpAppRn e1@(NegApp neg_arg neg_op)
- op2
- fix2@(Fixity prec2 dir2)
- e2
+---------------------------
+-- (- neg_arg) `op` e2
+mkOpAppRn e1@(NegApp neg_arg neg_name) op2 fix2 e2
| nofix_error
- = addErrRn (precParseErr (get neg_op,fix_neg) (get 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)
- | rearrange_me
- = mkOpAppRn neg_arg op2 fix2 e2 `thenRn` \ new_e ->
- returnRn (NegApp new_e neg_op)
+ | associate_right
+ = mkOpAppRn neg_arg op2 fix2 e2 `thenM` \ new_e ->
+ returnM (NegApp new_e neg_name)
+ where
+ (nofix_error, associate_right) = compareFixity negateFixity fix2
+
+---------------------------
+-- e1 `op` - neg_arg
+mkOpAppRn e1 op1 fix1 e2@(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
- fix_neg = Fixity 6 InfixL -- Precedence of unary negate is wired in as infixl 6!
- (nofix_error, rearrange_me) = compareFixity fix_neg fix2
+ (_, associate_right) = compareFixity fix1 negateFixity
+---------------------------
+-- Default case
mkOpAppRn e1 op fix e2 -- Default case, no rearrangment
- = ASSERT( right_op_ok fix e2 )
- returnRn (OpApp e1 op fix e2)
-
-get (HsVar n) = n
+ = ASSERT2( right_op_ok fix e2,
+ ppr e1 $$ text "---" $$ ppr op $$ text "---" $$ ppr fix $$ text "---" $$ ppr 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
+mkNegAppRn neg_arg neg_name
=
#ifdef DEBUG
- getModeRn `thenRn` \ mode ->
+ getModeRn `thenM` \ mode ->
ASSERT( not_op_app mode neg_arg )
#endif
- returnRn (NegApp neg_arg neg_op)
+ returnM (NegApp neg_arg neg_name)
not_op_app SourceMode (OpApp _ _ _ _) = False
not_op_app mode other = True
\end{code}
\begin{code}
-mkConOpPatRn :: RenamedPat -> Name -> Fixity -> RenamedPat
- -> RnMS s RenamedPat
-
-mkConOpPatRn p1@(ConOpPatIn p11 op1 fix1 p12)
- op2 fix2 p2
- | nofix_error
- = addErrRn (precParseErr (op1,fix1) (op2,fix2)) `thenRn_`
- returnRn (ConOpPatIn p1 op2 fix2 p2)
-
- | rearrange_me
- = mkConOpPatRn p12 op2 fix2 p2 `thenRn` \ new_p ->
- returnRn (ConOpPatIn p11 op1 fix1 new_p)
-
- where
- (nofix_error, rearrange_me) = compareFixity fix1 fix2
-
-mkConOpPatRn p1@(NegPatIn neg_arg)
- op2
- fix2@(Fixity prec2 dir2)
- p2
- | prec2 > 6 -- Precedence of unary - is wired in as 6!
- = addErrRn (precParseNegPatErr (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}
-
-\begin{code}
-checkPrecMatch :: Bool -> RdrName -> RdrNameMatch -> RnMS s ()
+checkPrecMatch :: Bool -> Name -> RenamedMatch -> RnM ()
checkPrecMatch False fn match
- = returnRn ()
-checkPrecMatch True op (PatMatch p1 (PatMatch p2 (GRHSMatch _)))
- = checkPrec op p1 False `thenRn_`
- checkPrec op p2 True
-checkPrecMatch True op _
- = 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) ->
+ = returnM ()
+
+checkPrecMatch True op (Match (p1:p2:_) _ _)
+ -- True indicates an infix lhs
+ = getModeRn `thenM` \ mode ->
+ -- See comments with rnExpr (OpApp ...)
+ if isInterfaceMode mode
+ then returnM ()
+ else checkPrec op p1 False `thenM_`
+ checkPrec op p2 True
+
+checkPrecMatch True op _ = panic "checkPrecMatch"
+
+checkPrec op (ConPatIn op1 (InfixCon _ _)) right
+ = lookupFixityRn op `thenM` \ op_fix@(Fixity op_prec op_dir) ->
+ lookupFixityRn op1 `thenM` \ op1_fix@(Fixity op1_prec op1_dir) ->
let
inf_ok = op1_prec > op_prec ||
(op1_prec == op_prec &&
(op1_dir == InfixR && op_dir == InfixR && right ||
op1_dir == InfixL && op_dir == InfixL && not right))
- info = (op,op_fix)
- info1 = (op1,op1_fix)
+ info = (ppr_op op, op_fix)
+ 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 <= 6) (precParseNegPatErr (op,op_fix))
+ checkErr inf_ok (precParseErr infol infor)
checkPrec op pat right
- = returnRn ()
-\end{code}
-
-Consider
- a `op1` b `op2` c
-
-(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 `cmp` prec2 of
- GT_ -> left
- LT_ -> right
- EQ_ -> case (dir1, dir2) of
- (InfixR, InfixR) -> right
- (InfixL, InfixL) -> left
- _ -> error_please
+ = returnM ()
+
+-- Check precedence of (arg op) or (op arg) respectively
+-- 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 direction section op arg
+ = case arg of
+ OpApp _ op fix _ -> go_for_it (ppr_op op) fix
+ NegApp _ _ -> go_for_it pp_prefix_minus negateFixity
+ other -> returnM ()
where
- right = (False, True)
- left = (False, False)
- error_please = (True, False)
+ 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}
+
%************************************************************************
%* *
-\subsubsection{Literals}
+\subsubsection{Assertion utils}
%* *
%************************************************************************
-When literals occur we have to make sure that the types and classes they involve
-are made available.
-
\begin{code}
-litOccurrence (HsChar _)
- = addImplicitOccRn charType_name
-
-litOccurrence (HsCharPrim _)
- = addImplicitOccRn (getName charPrimTyCon)
-
-litOccurrence (HsString _)
- = addImplicitOccRn listType_name `thenRn_`
- addImplicitOccRn charType_name
-
-litOccurrence (HsStringPrim _)
- = addImplicitOccRn (getName addrPrimTyCon)
-
-litOccurrence (HsInt _)
- = lookupImplicitOccRn numClass_RDR -- Int and Integer are forced in by Num
-
-litOccurrence (HsFrac _)
- = lookupImplicitOccRn fractionalClass_RDR `thenRn_`
- lookupImplicitOccRn ratioDataCon_RDR
- -- 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.
-
-litOccurrence (HsIntPrim _)
- = addImplicitOccRn (getName intPrimTyCon)
-
-litOccurrence (HsFloatPrim _)
- = addImplicitOccRn (getName floatPrimTyCon)
-
-litOccurrence (HsDoublePrim _)
- = addImplicitOccRn (getName doublePrimTyCon)
-
-litOccurrence (HsLitLit _)
- = lookupImplicitOccRn ccallableClass_RDR
+mkAssertErrorExpr :: RnM (RenamedHsExpr, FreeVars)
+-- Return an expression for (assertError "Foo.hs:27")
+mkAssertErrorExpr
+ = getSrcLocM `thenM` \ sloc ->
+ let
+ expr = HsApp (HsVar assertErrorName) (HsLit msg)
+ msg = HsStringPrim (mkFastString (stringToUtf8 (showSDoc (ppr sloc))))
+ in
+ returnM (expr, unitFV assertErrorName)
\end{code}
-
%************************************************************************
%* *
\subsubsection{Errors}
%************************************************************************
\begin{code}
-dupFieldErr str (dup:rest) sty
- = hcat [ptext SLIT("duplicate field name `"),
- ppr sty dup,
- ptext SLIT("' in record "), text str]
-
-negPatErr pat sty
- = sep [ptext SLIT("prefix `-' not applied to literal in pattern"), ppr sty pat]
-
-precParseNegPatErr op sty
- = hang (ptext SLIT("precedence parsing error"))
- 4 (hcat [ptext SLIT("prefix `-' has lower precedence than "),
- pp_op sty op,
- ptext SLIT(" in pattern")])
-
-precParseErr op1 op2 sty
- = hang (ptext SLIT("precedence parsing error"))
- 4 (hcat [ptext SLIT("cannot mix "), pp_op sty op1, ptext SLIT(" and "), pp_op sty op2,
- ptext SLIT(" in the same infix expression")])
-
-nonStdGuardErr guard sty
- = hang (ptext SLIT("accepting non-standard pattern guards (-fglasgow-exts to suppress this message)"))
- 4 (ppr sty guard)
-
-pp_op sty (op, fix) = hcat [ppr sty op, space, parens (ppr sty fix)]
+ppr_op op = quotes (ppr op) -- Here, op can be a Name or a (Var n), where n is a Name
+pp_prefix_minus = ptext SLIT("prefix `-'")
+
+nonStdGuardErr guard
+ = hang (ptext
+ SLIT("accepting non-standard pattern guards (-fglasgow-exts to suppress this message)")
+ ) 4 (ppr guard)
+
+patSynErr e
+ = sep [ptext SLIT("Pattern syntax in expression context:"),
+ nest 4 (ppr e)]
+
+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
+
+badIpBinds binds
+ = hang (ptext SLIT("Implicit-parameter bindings illegal in a parallel list comprehension:")) 4
+ (ppr binds)
\end{code}
projects / ghc-hetmet.git / blobdiff