#include "HsVersions.h"
+#ifdef GHCI
+import {-# SOURCE #-} TcSplice( runQuasiQuoteExpr )
+#endif /* GHCI */
+
import RnSource ( rnSrcDecls, rnSplice, checkTH )
-import RnBinds ( rnLocalBindsAndThen, rnValBinds,
- rnMatchGroup, trimWith )
+import RnBinds ( rnLocalBindsAndThen, rnValBindsLHS, rnValBindsRHS,
+ rnMatchGroup, makeMiniFixityEnv)
import HsSyn
-import RnHsSyn
import TcRnMonad
import RnEnv
-import OccName ( plusOccEnv )
-import RnNames ( getLocalDeclBinders, extendRdrEnvRn )
-import RnTypes ( rnHsTypeFVs, rnLPat, rnOverLit, rnPatsAndThen, rnLit,
- mkOpFormRn, mkOpAppRn, mkNegAppRn, checkSectionPrec,
- dupFieldErr, checkTupSize )
+import RnTypes ( rnHsTypeFVs,
+ mkOpFormRn, mkOpAppRn, mkNegAppRn, checkSectionPrec)
+import RnPat
import DynFlags ( DynFlag(..) )
import BasicTypes ( FixityDirection(..) )
-import SrcLoc ( SrcSpan )
import PrelNames ( thFAKE, hasKey, assertIdKey, assertErrorName,
loopAName, choiceAName, appAName, arrAName, composeAName, firstAName,
- negateName, thenMName, bindMName, failMName )
-#if defined(GHCI) && defined(BREAKPOINT)
-import PrelNames ( breakpointJumpName, breakpointCondJumpName
- , undefined_RDR, breakpointIdKey, breakpointCondIdKey )
-import UniqFM ( eltsUFM )
-import DynFlags ( GhcMode(..) )
-import Name ( isTyVarName )
-#endif
-import Name ( Name, nameOccName, nameIsLocalOrFrom )
+ negateName, thenMName, bindMName, failMName, groupWithName )
+
+import Name
import NameSet
-import RdrName ( RdrName, emptyGlobalRdrEnv, extendLocalRdrEnv, lookupLocalRdrEnv )
+import RdrName
import LoadIface ( loadInterfaceForName )
-import UniqFM ( isNullUFM )
-import UniqSet ( emptyUniqSet )
+import UniqSet
import List ( nub )
import Util ( isSingleton )
import ListSetOps ( removeDups )
import Maybes ( expectJust )
import Outputable
-import SrcLoc ( Located(..), unLoc, getLoc, cmpLocated )
+import SrcLoc
import FastString
import List ( unzip4 )
+import Control.Monad
\end{code}
+\begin{code}
+-- XXX
+thenM :: Monad a => a b -> (b -> a c) -> a c
+thenM = (>>=)
+
+thenM_ :: Monad a => a b -> a c -> a c
+thenM_ = (>>)
+
+returnM :: Monad m => a -> m a
+returnM = return
+
+mappM :: (Monad m) => (a -> m b) -> [a] -> m [b]
+mappM = mapM
+
+checkM :: Monad m => Bool -> m () -> m ()
+checkM = unless
+\end{code}
+
%************************************************************************
%* *
\subsubsection{Expressions}
let
acc' = acc `plusFV` fvExpr
in
- (grubby_seqNameSet acc' rnExprs') exprs acc' `thenM` \ (exprs', fvExprs) ->
+ acc' `seq` 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.
rnExpr (HsVar v)
= do name <- lookupOccRn v
- localRdrEnv <- getLocalRdrEnv
- lclEnv <- getLclEnv
ignore_asserts <- doptM Opt_IgnoreAsserts
- ignore_breakpoints <- doptM Opt_IgnoreBreakpoints
- ghcMode <- getGhcMode
- let conds = [ (name `hasKey` assertIdKey
- && not ignore_asserts,
- do (e, fvs) <- mkAssertErrorExpr
- return (e, fvs `addOneFV` name))
-#if defined(GHCI) && defined(BREAKPOINT)
- , (name `hasKey` breakpointIdKey
- && not ignore_breakpoints
- && ghcMode == Interactive,
- do let isWantedName = not.isTyVarName
- (e, fvs) <- mkBreakpointExpr (filter isWantedName (eltsUFM localRdrEnv))
- return (e, fvs `addOneFV` name)
- )
- , (name `hasKey` breakpointCondIdKey
- && not ignore_breakpoints
- && ghcMode == Interactive,
- do let isWantedName = not.isTyVarName
- (e, fvs) <- mkBreakpointCondExpr (filter isWantedName (eltsUFM localRdrEnv))
- return (e, fvs `addOneFV` name)
- )
-#endif
- ]
- case lookup True conds of
- Just action -> action
- Nothing -> return (HsVar name, unitFV name)
+ finish_var ignore_asserts name
+ where
+ finish_var ignore_asserts name
+ | ignore_asserts || not (name `hasKey` assertIdKey)
+ = return (HsVar name, unitFV name)
+ | otherwise
+ = do { (e, fvs) <- mkAssertErrorExpr
+ ; return (e, fvs `addOneFV` name) }
rnExpr (HsIPVar v)
= newIPNameRn v `thenM` \ name ->
returnM (HsIPVar name, emptyFVs)
+rnExpr (HsLit lit@(HsString s))
+ = do {
+ opt_OverloadedStrings <- doptM Opt_OverloadedStrings
+ ; if opt_OverloadedStrings then
+ rnExpr (HsOverLit (mkHsIsString s placeHolderType))
+ else -- Same as below
+ rnLit lit `thenM_`
+ returnM (HsLit lit, emptyFVs)
+ }
+
rnExpr (HsLit lit)
= rnLit lit `thenM_`
returnM (HsLit lit, emptyFVs)
rnBracket br_body `thenM` \ (body', fvs_e) ->
returnM (HsBracket body', fvs_e)
-rnExpr e@(HsSpliceE splice)
+rnExpr (HsSpliceE splice)
= rnSplice splice `thenM` \ (splice', fvs) ->
returnM (HsSpliceE splice', fvs)
+#ifndef GHCI
+rnExpr e@(HsQuasiQuoteE _) = pprPanic "Cant do quasiquotation without GHCi" (ppr e)
+#else
+rnExpr (HsQuasiQuoteE qq)
+ = rnQuasiQuote qq `thenM` \ (qq', fvs_qq) ->
+ runQuasiQuoteExpr qq' `thenM` \ (L _ expr') ->
+ rnExpr expr' `thenM` \ (expr'', fvs_expr) ->
+ returnM (expr'', fvs_qq `plusFV` fvs_expr)
+#endif /* GHCI */
+
rnExpr section@(SectionL expr op)
= rnLExpr expr `thenM` \ (expr', fvs_expr) ->
rnLExpr op `thenM` \ (op', fvs_op) ->
rnExpr (HsSCC lbl expr)
= rnLExpr expr `thenM` \ (expr', fvs_expr) ->
returnM (HsSCC lbl expr', fvs_expr)
+rnExpr (HsTickPragma info expr)
+ = rnLExpr expr `thenM` \ (expr', fvs_expr) ->
+ returnM (HsTickPragma info expr', fvs_expr)
rnExpr (HsLam matches)
= rnMatchGroup LambdaExpr matches `thenM` \ (matches', fvMatch) ->
rnLExpr expr `thenM` \ (expr',fvExpr) ->
returnM (HsLet binds' expr', fvExpr)
-rnExpr e@(HsDo do_or_lc stmts body _)
+rnExpr (HsDo do_or_lc stmts body _)
= do { ((stmts', body'), fvs) <- rnStmts do_or_lc stmts $
rnLExpr body
; return (HsDo do_or_lc stmts' body' placeHolderType, fvs) }
rnExpr (ExplicitList _ exps)
= rnExprs exps `thenM` \ (exps', fvs) ->
- returnM (ExplicitList placeHolderType exps', fvs `addOneFV` listTyCon_name)
+ returnM (ExplicitList placeHolderType exps', fvs)
rnExpr (ExplicitPArr _ exps)
= rnExprs exps `thenM` \ (exps', fvs) ->
returnM (ExplicitPArr placeHolderType exps', fvs)
-rnExpr e@(ExplicitTuple exps boxity)
- = checkTupSize tup_size `thenM_`
+rnExpr (ExplicitTuple exps boxity)
+ = checkTupSize (length exps) `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
+ returnM (ExplicitTuple exps' boxity, fvs)
rnExpr (RecordCon con_id _ rbinds)
- = lookupLocatedOccRn con_id `thenM` \ conname ->
- rnRbinds "construction" rbinds `thenM` \ (rbinds', fvRbinds) ->
- returnM (RecordCon conname noPostTcExpr rbinds',
- fvRbinds `addOneFV` unLoc conname)
+ = do { conname <- lookupLocatedOccRn con_id
+ ; (rbinds', fvRbinds) <- rnHsRecFields_Con conname rnLExpr rbinds
+ ; return (RecordCon conname noPostTcExpr rbinds',
+ fvRbinds `addOneFV` unLoc conname) }
-rnExpr (RecordUpd expr rbinds _ _)
- = rnLExpr expr `thenM` \ (expr', fvExpr) ->
- rnRbinds "update" rbinds `thenM` \ (rbinds', fvRbinds) ->
- returnM (RecordUpd expr' rbinds' placeHolderType placeHolderType,
- fvExpr `plusFV` fvRbinds)
+rnExpr (RecordUpd expr rbinds _ _ _)
+ = do { (expr', fvExpr) <- rnLExpr expr
+ ; (rbinds', fvRbinds) <- rnHsRecFields_Update rnLExpr rbinds
+ ; return (RecordUpd expr' rbinds' [] [] [],
+ fvExpr `plusFV` fvRbinds) }
rnExpr (ExprWithTySig expr pty)
- = rnLExpr expr `thenM` \ (expr', fvExpr) ->
- rnHsTypeFVs doc pty `thenM` \ (pty', fvTy) ->
- returnM (ExprWithTySig expr' pty', fvExpr `plusFV` fvTy)
+ = do { (pty', fvTy) <- rnHsTypeFVs doc pty
+ ; (expr', fvExpr) <- bindSigTyVarsFV (hsExplicitTvs pty') $
+ rnLExpr expr
+ ; return (ExprWithTySig expr' pty', fvExpr `plusFV` fvTy) }
where
doc = text "In an expression type signature"
\begin{code}
rnExpr e@EWildPat = patSynErr e
rnExpr e@(EAsPat {}) = patSynErr e
+rnExpr e@(EViewPat {}) = patSynErr e
rnExpr e@(ELazyPat {}) = patSynErr e
\end{code}
\begin{code}
rnExpr (HsProc pat body)
= newArrowScope $
- rnPatsAndThen ProcExpr [pat] $ \ [pat'] ->
+ rnPatsAndThen_LocalRightwards ProcExpr [pat] $ \ [pat'] ->
rnCmdTop body `thenM` \ (body',fvBody) ->
returnM (HsProc pat' body', fvBody)
returnM (HsArrForm op' fixity cmds', fvOp `plusFV` fvCmds)
rnExpr other = pprPanic "rnExpr: unexpected expression" (ppr other)
- -- DictApp, DictLam, TyApp, TyLam
+ -- HsWrap
\end{code}
%************************************************************************
\begin{code}
+rnCmdArgs :: [LHsCmdTop RdrName] -> RnM ([LHsCmdTop Name], FreeVars)
rnCmdArgs [] = returnM ([], emptyFVs)
rnCmdArgs (arg:args)
= rnCmdTop arg `thenM` \ (arg',fvArg) ->
rnCmdArgs args `thenM` \ (args',fvArgs) ->
returnM (arg':args', fvArg `plusFV` fvArgs)
-
+rnCmdTop :: LHsCmdTop RdrName -> RnM (LHsCmdTop Name, FreeVars)
rnCmdTop = wrapLocFstM rnCmdTop'
where
rnCmdTop' (HsCmdTop cmd _ _ _)
convertOpFormsCmd (HsPar c) = HsPar (convertOpFormsLCmd c)
--- gaw 2004
convertOpFormsCmd (HsCase exp matches)
= HsCase exp (convertOpFormsMatch matches)
-- caught by the type checker)
convertOpFormsCmd c = c
+convertOpFormsStmt :: StmtLR id id -> StmtLR id id
convertOpFormsStmt (BindStmt pat cmd _ _)
= BindStmt pat (convertOpFormsLCmd cmd) noSyntaxExpr noSyntaxExpr
convertOpFormsStmt (ExprStmt cmd _ _)
= RecStmt (map (fmap convertOpFormsStmt) stmts) lvs rvs es binds
convertOpFormsStmt stmt = stmt
+convertOpFormsMatch :: MatchGroup id -> MatchGroup id
convertOpFormsMatch (MatchGroup ms ty)
= MatchGroup (map (fmap convert) ms) ty
where convert (Match pat mty grhss)
= Match pat mty (convertOpFormsGRHSs grhss)
+convertOpFormsGRHSs :: GRHSs id -> GRHSs id
convertOpFormsGRHSs (GRHSs grhss binds)
= GRHSs (map convertOpFormsGRHS grhss) binds
+convertOpFormsGRHS :: Located (GRHS id) -> Located (GRHS id)
convertOpFormsGRHS = fmap convert
where
convert (GRHS stmts cmd) = GRHS stmts (convertOpFormsLCmd cmd)
methodNamesCmd :: HsCmd Name -> CmdNeeds
-methodNamesCmd cmd@(HsArrApp _arrow _arg _ HsFirstOrderApp _rtl)
+methodNamesCmd (HsArrApp _arrow _arg _ HsFirstOrderApp _rtl)
= emptyFVs
-methodNamesCmd cmd@(HsArrApp _arrow _arg _ HsHigherOrderApp _rtl)
+methodNamesCmd (HsArrApp _arrow _arg _ HsHigherOrderApp _rtl)
= unitFV appAName
-methodNamesCmd cmd@(HsArrForm {}) = emptyFVs
+methodNamesCmd (HsArrForm {}) = emptyFVs
methodNamesCmd (HsPar c) = methodNamesLCmd c
-methodNamesCmd (HsIf p c1 c2)
+methodNamesCmd (HsIf _ c1 c2)
= methodNamesLCmd c1 `plusFV` methodNamesLCmd c2 `addOneFV` choiceAName
-methodNamesCmd (HsLet b c) = methodNamesLCmd c
+methodNamesCmd (HsLet _ c) = methodNamesLCmd c
-methodNamesCmd (HsDo sc stmts body ty)
+methodNamesCmd (HsDo _ stmts body _)
= methodNamesStmts stmts `plusFV` methodNamesLCmd body
-methodNamesCmd (HsApp c e) = methodNamesLCmd c
+methodNamesCmd (HsApp c _) = methodNamesLCmd c
methodNamesCmd (HsLam match) = methodNamesMatch match
-methodNamesCmd (HsCase scrut matches)
+methodNamesCmd (HsCase _ matches)
= methodNamesMatch matches `addOneFV` choiceAName
-methodNamesCmd other = emptyFVs
+methodNamesCmd _ = 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 Name -> FreeVars
methodNamesMatch (MatchGroup ms _)
= plusFVs (map do_one ms)
where
- do_one (L _ (Match pats sig_ty grhss)) = methodNamesGRHSs grhss
+ do_one (L _ (Match _ _ grhss)) = methodNamesGRHSs grhss
-------------------------------------------------
-- gaw 2004
-methodNamesGRHSs (GRHSs grhss binds) = plusFVs (map methodNamesGRHS grhss)
+methodNamesGRHSs :: GRHSs Name -> FreeVars
+methodNamesGRHSs (GRHSs grhss _) = plusFVs (map methodNamesGRHS grhss)
-------------------------------------------------
-methodNamesGRHS (L _ (GRHS stmts rhs)) = methodNamesLCmd rhs
+
+methodNamesGRHS :: Located (GRHS Name) -> CmdNeeds
+methodNamesGRHS (L _ (GRHS _ rhs)) = methodNamesLCmd rhs
---------------------------------------------------
+methodNamesStmts :: [Located (StmtLR Name Name)] -> FreeVars
methodNamesStmts stmts = plusFVs (map methodNamesLStmt stmts)
---------------------------------------------------
+methodNamesLStmt :: Located (StmtLR Name Name) -> FreeVars
methodNamesLStmt = methodNamesStmt . unLoc
+methodNamesStmt :: StmtLR Name Name -> FreeVars
methodNamesStmt (ExprStmt cmd _ _) = methodNamesLCmd cmd
-methodNamesStmt (BindStmt pat cmd _ _) = methodNamesLCmd cmd
+methodNamesStmt (BindStmt _ cmd _ _) = methodNamesLCmd cmd
methodNamesStmt (RecStmt stmts _ _ _ _)
= 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
+methodNamesStmt (LetStmt _) = emptyFVs
+methodNamesStmt (ParStmt _) = emptyFVs
+methodNamesStmt (TransformStmt _ _ _) = emptyFVs
+methodNamesStmt (GroupStmt _ _) = emptyFVs
+ -- ParStmt, TransformStmt and GroupStmt can't occur in commands, but it's not convenient to error
-- here so we just do what's convenient
\end{code}
%************************************************************************
\begin{code}
+rnArithSeq :: ArithSeqInfo RdrName -> RnM (ArithSeqInfo Name, FreeVars)
rnArithSeq (From expr)
= rnLExpr expr `thenM` \ (expr', fvExpr) ->
returnM (From expr', fvExpr)
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 cmpLocated [ f | (f,_) <- rbinds ]
-
- field_dup_err dups = mappM_ (\f -> addLocErr f (dupFieldErr str)) dups
-
- 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 :: HsBracket RdrName -> RnM (HsBracket Name, FreeVars)
rnBracket (VarBr n) = do { name <- lookupOccRn n
; this_mod <- getModule
; checkM (nameIsLocalOrFrom this_mod name) $ -- Reason: deprecation checking asumes the
; return () } -- only way that is going to happen
; returnM (VarBr name, unitFV name) }
where
- msg = ptext SLIT("Need interface for Template Haskell quoted Name")
+ msg = ptext (sLit "Need interface for Template Haskell quoted Name")
rnBracket (ExpBr e) = do { (e', fvs) <- rnLExpr e
; return (ExpBr e', fvs) }
-rnBracket (PatBr p) = do { (p', fvs) <- rnLPat p
- ; return (PatBr p', fvs) }
+
+rnBracket (PatBr _) = do { addErr (ptext (sLit "Tempate Haskell pattern brackets are not supported yet"));
+ failM }
+
rnBracket (TypBr t) = do { (t', fvs) <- rnHsTypeFVs doc t
; return (TypBr t', fvs) }
where
- doc = ptext SLIT("In a Template-Haskell quoted type")
+ doc = ptext (sLit "In a Template-Haskell quoted type")
rnBracket (DecBr group)
- = do { gbl_env <- getGblEnv
-
- ; let gbl_env1 = gbl_env { tcg_mod = thFAKE }
- -- Note the thFAKE. The top-level names from the bracketed
- -- declarations will go into the name cache, and we don't want them to
- -- confuse the Names for the current module.
- -- By using a pretend module, thFAKE, we keep them safely out of the way.
-
- ; names <- getLocalDeclBinders gbl_env1 group
- ; rdr_env' <- extendRdrEnvRn emptyGlobalRdrEnv names
- -- Furthermore, the names in the bracket shouldn't conflict with
- -- existing top-level names E.g.
+ = do { gbl_env <- getGblEnv
+
+ ; let new_gbl_env = gbl_env { -- Set the module to thFAKE. The top-level names from the bracketed
+ -- declarations will go into the name cache, and we don't want them to
+ -- confuse the Names for the current module.
+ -- By using a pretend module, thFAKE, we keep them safely out of the way.
+ tcg_mod = thFAKE,
+
+ -- The emptyDUs is so that we just collect uses for this group alone
+ -- in the call to rnSrcDecls below
+ tcg_dus = emptyDUs }
+ ; setGblEnv new_gbl_env $ do {
+
+ -- In this situation we want to *shadow* top-level bindings.
-- foo = 1
- -- bar = [d| foo = 1|]
- -- But both 'foo's get a LocalDef provenance, so we'd get a complaint unless
- -- we start with an emptyGlobalRdrEnv
-
- ; setGblEnv (gbl_env { tcg_rdr_env = tcg_rdr_env gbl_env1 `plusOccEnv` rdr_env',
- tcg_dus = emptyDUs }) $ do
- -- Notice plusOccEnv, not plusGlobalRdrEnv. In this situation we want
- -- to *shadow* top-level bindings. (See the 'foo' example above.)
- -- If we don't shadow, we'll get an ambiguity complaint when we do
- -- a lookupTopBndrRn (which uses lookupGreLocalRn) on the binder of the 'foo'
- --
- -- Furthermore, arguably if the splice does define foo, that should hide
- -- any foo's further out
- --
- -- The emptyDUs is so that we just collect uses for this group alone
-
- { (tcg_env, group') <- rnSrcDecls group
- -- Discard the tcg_env; it contains only extra info about fixity
+ -- bar = [d| foo = 1 |]
+ -- If we don't shadow, we'll get an ambiguity complaint when we do
+ -- a lookupTopBndrRn (which uses lookupGreLocalRn) on the binder of the 'foo'
+ --
+ -- Furthermore, arguably if the splice does define foo, that should hide
+ -- any foo's further out
+ --
+ -- The shadowing is acheived by calling rnSrcDecls with True as the shadowing flag
+ ; (tcg_env, group') <- rnSrcDecls True group
+
+ -- Discard the tcg_env; it contains only extra info about fixity
; return (DecBr group', allUses (tcg_dus tcg_env)) } }
\end{code}
-- Used for cases *other* than recursive mdo
-- Implements nested scopes
-rnNormalStmts ctxt [] thing_inside
- = do { (thing, fvs) <- thing_inside
+rnNormalStmts _ [] thing_inside
+ = do { (thing, fvs) <- thing_inside
; return (([],thing), fvs) }
rnNormalStmts ctxt (L loc stmt : stmts) thing_inside
- = do { ((stmt', (stmts', thing)), fvs)
- <- rnStmt ctxt stmt $
- rnNormalStmts ctxt stmts thing_inside
+ = do { ((stmt', (stmts', thing)), fvs) <- rnStmt ctxt stmt $
+ rnNormalStmts ctxt stmts thing_inside
; return (((L loc stmt' : stmts'), thing), fvs) }
-
+
+
rnStmt :: HsStmtContext Name -> Stmt RdrName
-> RnM (thing, FreeVars)
-> RnM ((Stmt Name, thing), FreeVars)
-rnStmt ctxt (ExprStmt expr _ _) thing_inside
+rnStmt _ (ExprStmt expr _ _) thing_inside
= do { (expr', fv_expr) <- rnLExpr expr
; (then_op, fvs1) <- lookupSyntaxName thenMName
; (thing, fvs2) <- thing_inside
-- The binders do not scope over the expression
; (bind_op, fvs1) <- lookupSyntaxName bindMName
; (fail_op, fvs2) <- lookupSyntaxName failMName
- ; rnPatsAndThen (StmtCtxt ctxt) [pat] $ \ [pat'] -> do
+ ; rnPatsAndThen_LocalRightwards (StmtCtxt ctxt) [pat] $ \ [pat'] -> do
{ (thing, fvs3) <- thing_inside
; return ((BindStmt pat' expr' bind_op fail_op, thing),
fv_expr `plusFV` fvs1 `plusFV` fvs2 `plusFV` fvs3) }}
- -- fv_expr shouldn't really be filtered by the rnPatsAndThen
+ -- fv_expr shouldn't really be filtered by the rnPatsAndThen
-- but it does not matter because the names are unique
-rnStmt ctxt (LetStmt binds) thing_inside
- = do { checkErr (ok ctxt binds)
- (badIpBinds (ptext SLIT("a parallel list comprehension:")) binds)
- ; rnLocalBindsAndThen binds $ \ binds' -> do
+rnStmt ctxt (LetStmt binds) thing_inside
+ = do { checkLetStmt ctxt binds
+ ; rnLocalBindsAndThen binds $ \binds' -> do
{ (thing, fvs) <- thing_inside
- ; return ((LetStmt binds', thing), fvs) }}
- where
- -- We do not allow implicit-parameter bindings in a parallel
- -- list comprehension. I'm not sure what it might mean.
- ok (ParStmtCtxt _) (HsIPBinds _) = False
- ok _ _ = True
+ ; return ((LetStmt binds', thing), fvs) } }
rnStmt ctxt (RecStmt rec_stmts _ _ _ _) thing_inside
- = bindLocatedLocalsRn doc (collectLStmtsBinders rec_stmts) $ \ bndrs ->
- rn_rec_stmts bndrs rec_stmts `thenM` \ segs ->
- thing_inside `thenM` \ (thing, 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
- rec_stmt = RecStmt rec_stmts' later_vars fwd_vars [] emptyLHsBinds
- in
- returnM ((rec_stmt, thing), uses `plusFV` fvs)
- where
- doc = text "In a recursive do statement"
+ = do { checkRecStmt ctxt
+ ; rn_rec_stmts_and_then rec_stmts $ \ segs -> do
+ { (thing, fvs) <- thing_inside
+ ; 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
+ rec_stmt = RecStmt rec_stmts' later_vars fwd_vars [] emptyLHsBinds
+ ; return ((rec_stmt, thing), uses `plusFV` fvs) } }
rnStmt ctxt (ParStmt segs) thing_inside
- = do { opt_GlasgowExts <- doptM Opt_GlasgowExts
- ; checkM opt_GlasgowExts parStmtErr
- ; orig_lcl_env <- getLocalRdrEnv
- ; ((segs',thing), fvs) <- go orig_lcl_env [] segs
+ = do { checkParStmt ctxt
+ ; ((segs', thing), fvs) <- rnParallelStmts (ParStmtCtxt ctxt) segs thing_inside
; return ((ParStmt segs', thing), fvs) }
+
+rnStmt ctxt (TransformStmt (stmts, _) usingExpr maybeByExpr) thing_inside = do
+ checkTransformStmt ctxt
+
+ (usingExpr', fv_usingExpr) <- rnLExpr usingExpr
+ ((stmts', binders, (maybeByExpr', thing)), fvs) <-
+ rnNormalStmtsAndFindUsedBinders (TransformStmtCtxt ctxt) stmts $ \_unshadowed_bndrs -> do
+ (maybeByExpr', fv_maybeByExpr) <- rnMaybeLExpr maybeByExpr
+ (thing, fv_thing) <- thing_inside
+
+ return ((maybeByExpr', thing), fv_maybeByExpr `plusFV` fv_thing)
+
+ return ((TransformStmt (stmts', binders) usingExpr' maybeByExpr', thing), fv_usingExpr `plusFV` fvs)
where
--- type ParSeg id = [([LStmt id], [id])]
--- go :: NameSet -> [ParSeg RdrName]
--- -> RnM (([ParSeg Name], thing), FreeVars)
-
- go orig_lcl_env bndrs []
- = do { let { (bndrs', dups) = removeDups cmpByOcc bndrs
- ; inner_env = extendLocalRdrEnv orig_lcl_env bndrs' }
- ; mappM dupErr dups
- ; (thing, fvs) <- setLocalRdrEnv inner_env thing_inside
- ; return (([], thing), fvs) }
-
- go orig_lcl_env bndrs_so_far ((stmts, _) : segs)
- = do { ((stmts', (bndrs, segs', thing)), fvs)
- <- rnNormalStmts par_ctxt stmts $ do
- { -- Find the Names that are bound by stmts
- lcl_env <- getLocalRdrEnv
- ; let { rdr_bndrs = collectLStmtsBinders stmts
- ; bndrs = map ( expectJust "rnStmt"
- . lookupLocalRdrEnv lcl_env
- . unLoc) rdr_bndrs
- ; new_bndrs = nub bndrs ++ bndrs_so_far
- -- The nub is because there might be shadowing
- -- x <- e1; x <- e2
- -- So we'll look up (Unqual x) twice, getting
- -- the second binding both times, which is the
- } -- one we want
-
- -- Typecheck the thing inside, passing on all
- -- the Names bound, but separately; revert the envt
- ; ((segs', thing), fvs) <- setLocalRdrEnv orig_lcl_env $
- go orig_lcl_env new_bndrs segs
-
- -- Figure out which of the bound names are used
- ; let used_bndrs = filter (`elemNameSet` fvs) bndrs
- ; return ((used_bndrs, segs', thing), fvs) }
-
- ; let seg' = (stmts', bndrs)
- ; return (((seg':segs'), thing),
- delListFromNameSet fvs bndrs) }
-
- par_ctxt = ParStmtCtxt ctxt
-
- cmpByOcc n1 n2 = nameOccName n1 `compare` nameOccName n2
- dupErr vs = addErr (ptext SLIT("Duplicate binding in parallel list comprehension for:")
- <+> quotes (ppr (head vs)))
+ rnMaybeLExpr Nothing = return (Nothing, emptyFVs)
+ rnMaybeLExpr (Just expr) = do
+ (expr', fv_expr) <- rnLExpr expr
+ return (Just expr', fv_expr)
+
+rnStmt ctxt (GroupStmt (stmts, _) groupByClause) thing_inside = do
+ checkTransformStmt ctxt
+
+ -- We must rename the using expression in the context before the transform is begun
+ groupByClauseAction <-
+ case groupByClause of
+ GroupByNothing usingExpr -> do
+ (usingExpr', fv_usingExpr) <- rnLExpr usingExpr
+ (return . return) (GroupByNothing usingExpr', fv_usingExpr)
+ GroupBySomething eitherUsingExpr byExpr -> do
+ (eitherUsingExpr', fv_eitherUsingExpr) <-
+ case eitherUsingExpr of
+ Right _ -> return (Right $ HsVar groupWithName, unitNameSet groupWithName)
+ Left usingExpr -> do
+ (usingExpr', fv_usingExpr) <- rnLExpr usingExpr
+ return (Left usingExpr', fv_usingExpr)
+
+ return $ do
+ (byExpr', fv_byExpr) <- rnLExpr byExpr
+ return (GroupBySomething eitherUsingExpr' byExpr', fv_eitherUsingExpr `plusFV` fv_byExpr)
+
+ -- We only use rnNormalStmtsAndFindUsedBinders to get unshadowed_bndrs, so
+ -- perhaps we could refactor this to use rnNormalStmts directly?
+ ((stmts', _, (groupByClause', usedBinderMap, thing)), fvs) <-
+ rnNormalStmtsAndFindUsedBinders (TransformStmtCtxt ctxt) stmts $ \unshadowed_bndrs -> do
+ (groupByClause', fv_groupByClause) <- groupByClauseAction
+
+ unshadowed_bndrs' <- mapM newLocalName unshadowed_bndrs
+ let binderMap = zip unshadowed_bndrs unshadowed_bndrs'
+
+ -- Bind the "thing" inside a context where we have REBOUND everything
+ -- bound by the statements before the group. This is necessary since after
+ -- the grouping the same identifiers actually have different meanings
+ -- i.e. they refer to lists not singletons!
+ (thing, fv_thing) <- bindLocalNames unshadowed_bndrs' thing_inside
+
+ -- We remove entries from the binder map that are not used in the thing_inside.
+ -- We can then use that usage information to ensure that the free variables do
+ -- not contain the things we just bound, but do contain the things we need to
+ -- make those bindings (i.e. the corresponding non-listy variables)
+
+ -- Note that we also retain those entries which have an old binder in our
+ -- own free variables (the using or by expression). This is because this map
+ -- is reused in the desugarer to create the type to bind from the statements
+ -- that occur before this one. If the binders we need are not in the map, they
+ -- will never get bound into our desugared expression and hence the simplifier
+ -- crashes as we refer to variables that don't exist!
+ let usedBinderMap = filter
+ (\(old_binder, new_binder) ->
+ (new_binder `elemNameSet` fv_thing) ||
+ (old_binder `elemNameSet` fv_groupByClause)) binderMap
+ (usedOldBinders, usedNewBinders) = unzip usedBinderMap
+ real_fv_thing = (delListFromNameSet fv_thing usedNewBinders) `plusFV` (mkNameSet usedOldBinders)
+
+ return ((groupByClause', usedBinderMap, thing), fv_groupByClause `plusFV` real_fv_thing)
+
+ traceRn (text "rnStmt: implicitly rebound these used binders:" <+> ppr usedBinderMap)
+ return ((GroupStmt (stmts', usedBinderMap) groupByClause', thing), fvs)
+
+rnNormalStmtsAndFindUsedBinders :: HsStmtContext Name
+ -> [LStmt RdrName]
+ -> ([Name] -> RnM (thing, FreeVars))
+ -> RnM (([LStmt Name], [Name], thing), FreeVars)
+rnNormalStmtsAndFindUsedBinders ctxt stmts thing_inside = do
+ ((stmts', (used_bndrs, inner_thing)), fvs) <- rnNormalStmts ctxt stmts $ do
+ -- Find the Names that are bound by stmts that
+ -- by assumption we have just renamed
+ local_env <- getLocalRdrEnv
+ let
+ stmts_binders = collectLStmtsBinders stmts
+ bndrs = map (expectJust "rnStmt"
+ . lookupLocalRdrEnv local_env
+ . unLoc) stmts_binders
+
+ -- If shadow, we'll look up (Unqual x) twice, getting
+ -- the second binding both times, which is the
+ -- one we want
+ unshadowed_bndrs = nub bndrs
+
+ -- Typecheck the thing inside, passing on all
+ -- the Names bound before it for its information
+ (thing, fvs) <- thing_inside unshadowed_bndrs
+
+ -- Figure out which of the bound names are used
+ -- after the statements we renamed
+ let used_bndrs = filter (`elemNameSet` fvs) bndrs
+ return ((used_bndrs, thing), fvs)
+
+ -- Flatten the tuple returned by the above call a bit!
+ return ((stmts', used_bndrs, inner_thing), fvs)
+
+rnParallelStmts :: HsStmtContext Name -> [([LStmt RdrName], [RdrName])]
+ -> RnM (thing, FreeVars)
+ -> RnM (([([LStmt Name], [Name])], thing), FreeVars)
+rnParallelStmts ctxt segs thing_inside = do
+ orig_lcl_env <- getLocalRdrEnv
+ go orig_lcl_env [] segs
+ where
+ go orig_lcl_env bndrs [] = do
+ let (bndrs', dups) = removeDups cmpByOcc bndrs
+ inner_env = extendLocalRdrEnv orig_lcl_env bndrs'
+
+ mappM dupErr dups
+ (thing, fvs) <- setLocalRdrEnv inner_env thing_inside
+ return (([], thing), fvs)
+
+ go orig_lcl_env bndrs_so_far ((stmts, _) : segs) = do
+ ((stmts', bndrs, (segs', thing)), fvs) <- rnNormalStmtsAndFindUsedBinders ctxt stmts $ \new_bndrs -> do
+ -- Typecheck the thing inside, passing on all
+ -- the Names bound, but separately; revert the envt
+ setLocalRdrEnv orig_lcl_env $ do
+ go orig_lcl_env (new_bndrs ++ bndrs_so_far) segs
+
+ let seg' = (stmts', bndrs)
+ return (((seg':segs'), thing), delListFromNameSet fvs bndrs)
+
+ cmpByOcc n1 n2 = nameOccName n1 `compare` nameOccName n2
+ dupErr vs = addErr (ptext (sLit "Duplicate binding in parallel list comprehension for:")
+ <+> quotes (ppr (head vs)))
\end{code}
----------------------------------------------------
+
rnMDoStmts :: [LStmt RdrName]
-> RnM (thing, FreeVars)
-> RnM (([LStmt Name], thing), FreeVars)
rnMDoStmts stmts thing_inside
- = -- 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 (collectLStmtsBinders stmts) $ \ bndrs ->
- do {
- -- 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.)
- segs <- rn_rec_stmts bndrs stmts
+ = -- Step1: Bring all the binders of the mdo into scope
+ -- (Remember that this also removes the binders from the
+ -- finally-returned free-vars.)
+ -- And 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_and_then stmts $ \ segs -> do {
; (thing, fvs_later) <- thing_inside
; let
- -- Step 3: Fill in the fwd refs.
+ -- Step 2: 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
+ -- Step 3: 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
+ -- Step 4: 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
(stmts', fvs) = segsToStmts grouped_segs fvs_later
; return ((stmts', thing), fvs) }
- where
- doc = text "In a recursive mdo-expression"
---------------------------------------------
-rn_rec_stmts :: [Name] -> [LStmt RdrName] -> RnM [Segment (LStmt Name)]
-rn_rec_stmts bndrs stmts = mappM (rn_rec_stmt bndrs) stmts `thenM` \ segs_s ->
- returnM (concat segs_s)
-----------------------------------------------------
-rn_rec_stmt :: [Name] -> LStmt RdrName -> RnM [Segment (LStmt Name)]
+-- wrapper that does both the left- and right-hand sides
+rn_rec_stmts_and_then :: [LStmt RdrName]
+ -- assumes that the FreeVars returned includes
+ -- the FreeVars of the Segments
+ -> ([Segment (LStmt Name)] -> RnM (a, FreeVars))
+ -> RnM (a, FreeVars)
+rn_rec_stmts_and_then s cont
+ = do { -- (A) Make the mini fixity env for all of the stmts
+ fix_env <- makeMiniFixityEnv (collectRecStmtsFixities s)
+
+ -- (B) Do the LHSes
+ ; new_lhs_and_fv <- rn_rec_stmts_lhs fix_env s
+
+ -- ...bring them and their fixities into scope
+ ; let bound_names = map unLoc $ collectLStmtsBinders (map fst new_lhs_and_fv)
+ ; bindLocalNamesFV_WithFixities bound_names fix_env $ do
+
+ -- (C) do the right-hand-sides and thing-inside
+ { segs <- rn_rec_stmts bound_names new_lhs_and_fv
+ ; (res, fvs) <- cont segs
+ ; warnUnusedLocalBinds bound_names fvs
+ ; return (res, fvs) }}
+
+-- get all the fixity decls in any Let stmt
+collectRecStmtsFixities :: [LStmtLR RdrName RdrName] -> [LFixitySig RdrName]
+collectRecStmtsFixities l =
+ foldr (\ s -> \acc -> case s of
+ (L _ (LetStmt (HsValBinds (ValBindsIn _ sigs)))) ->
+ foldr (\ sig -> \ acc -> case sig of
+ (L loc (FixSig s)) -> (L loc s) : acc
+ _ -> acc) acc sigs
+ _ -> acc) [] l
+
+-- left-hand sides
+
+rn_rec_stmt_lhs :: MiniFixityEnv
+ -> LStmt RdrName
+ -- rename LHS, and return its FVs
+ -- Warning: we will only need the FreeVars below in the case of a BindStmt,
+ -- so we don't bother to compute it accurately in the other cases
+ -> RnM [(LStmtLR Name RdrName, FreeVars)]
+
+rn_rec_stmt_lhs _ (L loc (ExprStmt expr a b)) = return [(L loc (ExprStmt expr a b),
+ -- this is actually correct
+ emptyFVs)]
+
+rn_rec_stmt_lhs fix_env (L loc (BindStmt pat expr a b))
+ = do
+ -- should the ctxt be MDo instead?
+ (pat', fv_pat) <- rnBindPat (localRecNameMaker fix_env) pat
+ return [(L loc (BindStmt pat' expr a b),
+ fv_pat)]
+
+rn_rec_stmt_lhs _ (L _ (LetStmt binds@(HsIPBinds _)))
+ = do { addErr (badIpBinds (ptext (sLit "an mdo expression")) binds)
+ ; failM }
+
+rn_rec_stmt_lhs fix_env (L loc (LetStmt (HsValBinds binds)))
+ = do binds' <- rnValBindsLHS fix_env binds
+ return [(L loc (LetStmt (HsValBinds binds')),
+ -- Warning: this is bogus; see function invariant
+ emptyFVs
+ )]
+
+rn_rec_stmt_lhs fix_env (L _ (RecStmt stmts _ _ _ _)) -- Flatten Rec inside Rec
+ = rn_rec_stmts_lhs fix_env stmts
+
+rn_rec_stmt_lhs _ stmt@(L _ (ParStmt _)) -- Syntactically illegal in mdo
+ = pprPanic "rn_rec_stmt" (ppr stmt)
+
+rn_rec_stmt_lhs _ stmt@(L _ (TransformStmt _ _ _)) -- Syntactically illegal in mdo
+ = pprPanic "rn_rec_stmt" (ppr stmt)
+
+rn_rec_stmt_lhs _ stmt@(L _ (GroupStmt _ _)) -- Syntactically illegal in mdo
+ = pprPanic "rn_rec_stmt" (ppr stmt)
+
+rn_rec_stmt_lhs _ (L _ (LetStmt EmptyLocalBinds))
+ = panic "rn_rec_stmt LetStmt EmptyLocalBinds"
+
+rn_rec_stmts_lhs :: MiniFixityEnv
+ -> [LStmt RdrName]
+ -> RnM [(LStmtLR Name RdrName, FreeVars)]
+rn_rec_stmts_lhs fix_env stmts =
+ let boundNames = collectLStmtsBinders stmts
+ doc = text "In a recursive mdo-expression"
+ in do
+ -- First do error checking: we need to check for dups here because we
+ -- don't bind all of the variables from the Stmt at once
+ -- with bindLocatedLocals.
+ checkDupRdrNames doc boundNames
+ mappM (rn_rec_stmt_lhs fix_env) stmts `thenM` \ ls -> returnM (concat ls)
+
+
+-- right-hand-sides
+
+rn_rec_stmt :: [Name] -> LStmtLR Name RdrName -> FreeVars -> 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 all_bndrs (L loc (ExprStmt expr _ _))
- = rnLExpr expr `thenM` \ (expr', fvs) ->
+rn_rec_stmt _ (L loc (ExprStmt expr _ _)) _
+ = rnLExpr expr `thenM` \ (expr', fvs) ->
lookupSyntaxName thenMName `thenM` \ (then_op, fvs1) ->
returnM [(emptyNameSet, fvs `plusFV` fvs1, emptyNameSet,
L loc (ExprStmt expr' then_op placeHolderType))]
-rn_rec_stmt all_bndrs (L loc (BindStmt pat expr _ _))
+rn_rec_stmt _ (L loc (BindStmt pat' expr _ _)) fv_pat
= rnLExpr expr `thenM` \ (expr', fv_expr) ->
- rnLPat pat `thenM` \ (pat', fv_pat) ->
lookupSyntaxName bindMName `thenM` \ (bind_op, fvs1) ->
lookupSyntaxName failMName `thenM` \ (fail_op, fvs2) ->
let
returnM [(bndrs, fvs, bndrs `intersectNameSet` fvs,
L loc (BindStmt pat' expr' bind_op fail_op))]
-rn_rec_stmt all_bndrs (L loc (LetStmt binds@(HsIPBinds _)))
- = do { addErr (badIpBinds (ptext SLIT("an mdo expression")) binds)
+rn_rec_stmt _ (L _ (LetStmt binds@(HsIPBinds _))) _
+ = do { addErr (badIpBinds (ptext (sLit "an mdo expression")) binds)
; failM }
-rn_rec_stmt all_bndrs (L loc (LetStmt (HsValBinds binds)))
- = rnValBinds (trimWith all_bndrs) binds `thenM` \ (binds', du_binds) ->
- returnM [(duDefs du_binds, duUses du_binds,
- emptyNameSet, L loc (LetStmt (HsValBinds binds')))]
+rn_rec_stmt all_bndrs (L loc (LetStmt (HsValBinds binds'))) _ = do
+ (binds', du_binds) <-
+ -- fixities and unused are handled above in rn_rec_stmts_and_then
+ rnValBindsRHS all_bndrs binds'
+ returnM [(duDefs du_binds, duUses du_binds,
+ emptyNameSet, L loc (LetStmt (HsValBinds binds')))]
-rn_rec_stmt all_bndrs (L loc (RecStmt stmts _ _ _ _)) -- Flatten Rec inside Rec
- = rn_rec_stmts all_bndrs stmts
+-- no RecStmt case becuase they get flattened above when doing the LHSes
+rn_rec_stmt _ stmt@(L _ (RecStmt _ _ _ _ _)) _
+ = pprPanic "rn_rec_stmt: RecStmt" (ppr stmt)
-rn_rec_stmt all_bndrs stmt@(L _ (ParStmt _)) -- Syntactically illegal in mdo
- = pprPanic "rn_rec_stmt" (ppr stmt)
+rn_rec_stmt _ stmt@(L _ (ParStmt _)) _ -- Syntactically illegal in mdo
+ = pprPanic "rn_rec_stmt: ParStmt" (ppr stmt)
+
+rn_rec_stmt _ stmt@(L _ (TransformStmt _ _ _)) _ -- Syntactically illegal in mdo
+ = pprPanic "rn_rec_stmt: TransformStmt" (ppr stmt)
+
+rn_rec_stmt _ stmt@(L _ (GroupStmt _ _)) _ -- Syntactically illegal in mdo
+ = pprPanic "rn_rec_stmt: GroupStmt" (ppr stmt)
+
+rn_rec_stmt _ (L _ (LetStmt EmptyLocalBinds)) _
+ = panic "rn_rec_stmt: LetStmt EmptyLocalBinds"
+
+rn_rec_stmts :: [Name] -> [(LStmtLR Name RdrName, FreeVars)] -> RnM [Segment (LStmt Name)]
+rn_rec_stmts bndrs stmts = mappM (uncurry (rn_rec_stmt bndrs)) stmts `thenM` \ segs_s ->
+ returnM (concat segs_s)
---------------------------------------------
addFwdRefs :: [Segment a] -> [Segment a]
%************************************************************************
%* *
-\subsubsection{breakpoint utils}
+\subsubsection{Assertion utils}
%* *
%************************************************************************
\begin{code}
-#if defined(GHCI) && defined(BREAKPOINT)
-mkBreakpointExpr :: [Name] -> RnM (HsExpr Name, FreeVars)
-mkBreakpointExpr = mkBreakpointExpr' breakpointJumpName
-
-mkBreakpointCondExpr :: [Name] -> RnM (HsExpr Name, FreeVars)
-mkBreakpointCondExpr = mkBreakpointExpr' breakpointCondJumpName
-
-mkBreakpointExpr' :: Name -> [Name] -> RnM (HsExpr Name, FreeVars)
-mkBreakpointExpr' breakpointFunc scope
- = do sloc <- getSrcSpanM
- undef <- lookupOccRn undefined_RDR
- let inLoc = L sloc
- lHsApp x y = inLoc (HsApp x y)
- mkExpr fnName args = mkExpr' fnName (reverse args)
- mkExpr' fnName [] = inLoc (HsVar fnName)
- mkExpr' fnName (arg:args)
- = lHsApp (mkExpr' fnName args) (inLoc arg)
- expr = unLoc $ mkExpr breakpointFunc [mkScopeArg scope, HsVar undef, msg]
- mkScopeArg args = unLoc $ mkExpr undef (map HsVar args)
- msg = srcSpanLit sloc
- return (expr, emptyFVs)
-#endif
-
-srcSpanLit :: SrcSpan -> HsExpr Name
-srcSpanLit span = HsLit (HsString (mkFastString (showSDoc (ppr span))))
-
srcSpanPrimLit :: SrcSpan -> HsExpr Name
srcSpanPrimLit span = HsLit (HsStringPrim (mkFastString (showSDoc (ppr span))))
-\end{code}
-
-%************************************************************************
-%* *
-\subsubsection{Assertion utils}
-%* *
-%************************************************************************
-\begin{code}
mkAssertErrorExpr :: RnM (HsExpr Name, FreeVars)
-- Return an expression for (assertError "Foo.hs:27")
mkAssertErrorExpr
%************************************************************************
\begin{code}
-patSynErr e = do { addErr (sep [ptext SLIT("Pattern syntax in expression context:"),
+
+----------------------
+-- Checking when a particular Stmt is ok
+checkLetStmt :: HsStmtContext Name -> HsLocalBinds RdrName -> RnM ()
+checkLetStmt (ParStmtCtxt _) (HsIPBinds binds) = addErr (badIpBinds (ptext (sLit "a parallel list comprehension:")) binds)
+checkLetStmt _ctxt _binds = return ()
+ -- We do not allow implicit-parameter bindings in a parallel
+ -- list comprehension. I'm not sure what it might mean.
+
+---------
+checkRecStmt :: HsStmtContext Name -> RnM ()
+checkRecStmt (MDoExpr {}) = return () -- Recursive stmt ok in 'mdo'
+checkRecStmt (DoExpr {}) = return () -- ..and in 'do' but only because of arrows:
+ -- proc x -> do { ...rec... }
+ -- We don't have enough context to distinguish this situation here
+ -- so we leave it to the type checker
+checkRecStmt ctxt = addErr msg
+ where
+ msg = ptext (sLit "Illegal 'rec' stmt in") <+> pprStmtContext ctxt
+
+---------
+checkParStmt :: HsStmtContext Name -> RnM ()
+checkParStmt _
+ = do { parallel_list_comp <- doptM Opt_ParallelListComp
+ ; checkErr parallel_list_comp msg }
+ where
+ msg = ptext (sLit "Illegal parallel list comprehension: use -XParallelListComp")
+
+---------
+checkTransformStmt :: HsStmtContext Name -> RnM ()
+checkTransformStmt ListComp -- Ensure we are really within a list comprehension because otherwise the
+ -- desugarer will break when we come to operate on a parallel array
+ = do { transform_list_comp <- doptM Opt_TransformListComp
+ ; checkErr transform_list_comp msg }
+ where
+ msg = ptext (sLit "Illegal transform or grouping list comprehension: use -XTransformListComp")
+checkTransformStmt (ParStmtCtxt ctxt) = checkTransformStmt ctxt -- Ok to nest inside a parallel comprehension
+checkTransformStmt (TransformStmtCtxt ctxt) = checkTransformStmt ctxt -- Ok to nest inside a parallel comprehension
+checkTransformStmt ctxt = addErr msg
+ where
+ msg = ptext (sLit "Illegal transform or grouping in") <+> pprStmtContext ctxt
+
+---------
+patSynErr :: HsExpr RdrName -> RnM (HsExpr Name, FreeVars)
+patSynErr e = do { addErr (sep [ptext (sLit "Pattern syntax in expression context:"),
nest 4 (ppr e)])
; return (EWildPat, emptyFVs) }
-parStmtErr = addErr (ptext SLIT("Illegal parallel list comprehension: use -fglasgow-exts"))
-
+badIpBinds :: Outputable a => SDoc -> a -> SDoc
badIpBinds what binds
- = hang (ptext SLIT("Implicit-parameter bindings illegal in") <+> what)
+ = hang (ptext (sLit "Implicit-parameter bindings illegal in") <+> what)
2 (ppr binds)
\end{code}