X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=ghc%2Fcompiler%2Frename%2FRnExpr.lhs;h=59d0dd180fdf58b020dba225d4a8a9fffbe2aa19;hb=3721dd37a707d2aacb5cac814410a78096e28a2c;hp=e67f32e165e58bfd194b7ab4e9b56d32b061eb1c;hpb=203a687fbdb9bf54592f907302d8e47e174bb549;p=ghc-hetmet.git

diff --git a/ghc/compiler/rename/RnExpr.lhs b/ghc/compiler/rename/RnExpr.lhs
index e67f32e..59d0dd1 100644
--- a/ghc/compiler/rename/RnExpr.lhs
+++ b/ghc/compiler/rename/RnExpr.lhs
@@ -11,51 +11,45 @@ free variables.
 
 \begin{code}
 module RnExpr (
-	rnMatch, rnGRHSs, rnExpr, rnExprs, rnStmts,
-	checkPrecMatch
+	rnMatch, rnGRHSs, rnLExpr, rnExpr, rnStmts,
+	checkPrecMatch, checkTH
    ) where
 
 #include "HsVersions.h"
 
-import {-# SOURCE #-} RnSource  ( rnSrcDecls, rnBindsAndThen, rnBinds ) 
+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 TcRnMonad
 import RnEnv
+import OccName		( plusOccEnv )
 import RnNames		( importsFromLocalDecls )
-import RnTypes		( rnHsTypeFVs, rnPat, litFVs, rnOverLit, rnPatsAndThen,
-			  dupFieldErr, precParseErr, sectionPrecErr, patSigErr )
-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,
+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 )
-#ifdef GHCI
-import DsMeta		( qTyConName )
-#endif
 import Name		( Name, nameOccName )
 import NameSet
+import RdrName		( RdrName )
 import UnicodeUtil	( stringToUtf8 )
 import UniqFM		( isNullUFM )
 import UniqSet		( emptyUniqSet )
 import Util		( isSingleton )
-import List		( intersectBy, unzip4 )
 import ListSetOps	( removeDups )
 import Outputable
+import SrcLoc		( Located(..), unLoc, getLoc, combineLocs, cmpLocated )
 import FastString
+
+import List		( unzip4 )
 \end{code}
 
 
@@ -66,28 +60,28 @@ import FastString
 ************************************************************************
 
 \begin{code}
-rnMatch :: HsMatchContext Name -> RdrNameMatch -> RnM (RenamedMatch, FreeVars)
-
-rnMatch ctxt match@(Match pats maybe_rhs_sig grhss)
-  = addSrcLoc (getMatchLoc match)	$
+rnMatch :: HsMatchContext Name -> LMatch RdrName -> RnM (LMatch Name, FreeVars)
+rnMatch ctxt  = wrapLocFstM (rnMatch' ctxt)
 
+rnMatch' ctxt match@(Match pats maybe_rhs_sig grhss)
+  = 
 	-- Deal with the rhs type signature
-    bindPatSigTyVars rhs_sig_tys	$ 
+    bindPatSigTyVarsFV 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_`
+		| otherwise	  -> addLocErr ty patSigErr	`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) ->
+    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 bindPatSigTyVars and rnPatsAndThen will remove the bound FVs
+	-- The bindPatSigTyVarsFV and rnPatsAndThen will remove the bound FVs
   where
      rhs_sig_tys =  case maybe_rhs_sig of
 			Nothing -> []
@@ -103,28 +97,30 @@ rnMatch ctxt match@(Match pats maybe_rhs_sig grhss)
 %************************************************************************
 
 \begin{code}
-rnGRHSs :: HsMatchContext Name -> RdrNameGRHSs -> RnM (RenamedGRHSs, FreeVars)
+rnGRHSs :: HsMatchContext Name -> GRHSs RdrName -> RnM (GRHSs Name, FreeVars)
 
 rnGRHSs ctxt (GRHSs grhss binds _)
-  = rnBindsAndThen binds	$ \ binds' ->
+  = rnBindGroupsAndThen 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 ->
+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' locn, 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 [ResultStmt _ _]                 = True
-    is_standard_guard [ExprStmt _ _ _, ResultStmt _ _] = 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}
 
 %************************************************************************
@@ -134,12 +130,12 @@ rnGRHS ctxt (GRHS guarded locn)
 %************************************************************************
 
 \begin{code}
-rnExprs :: [RdrNameHsExpr] -> RnM ([RenamedHsExpr], FreeVars)
+rnExprs :: [LHsExpr RdrName] -> RnM ([LHsExpr Name], FreeVars)
 rnExprs ls = rnExprs' ls emptyUniqSet
  where
   rnExprs' [] acc = returnM ([], acc)
   rnExprs' (expr:exprs) acc
-   = rnExpr expr 	        `thenM` \ (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
@@ -157,13 +153,19 @@ grubby_seqNameSet ns result | isNullUFM ns = result
 Variables. We look up the variable and return the resulting name. 
 
 \begin{code}
-rnExpr :: RdrNameHsExpr -> RnM (RenamedHsExpr, FreeVars)
+rnLExpr :: LHsExpr RdrName -> RnM (LHsExpr Name, FreeVars)
+rnLExpr = wrapLocFstM rnExpr
+
+rnExpr :: HsExpr RdrName -> RnM (HsExpr Name, FreeVars)
 
 rnExpr (HsVar v)
   = lookupOccRn v	`thenM` \ name ->
-    if name `hasKey` assertIdKey && not opt_IgnoreAsserts then
+    doptM Opt_IgnoreAsserts `thenM` \ ignore_asserts ->
+    if name `hasKey` assertIdKey && not ignore_asserts then
 	-- We expand it to (GHC.Err.assertError location_string)
-        mkAssertErrorExpr
+        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.  Even if the Id was 'assert', if we are 
 	-- ignoring assertions we leave it as GHC.Base.assert; 
@@ -171,17 +173,12 @@ rnExpr (HsVar v)
        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)
+  = newIPNameRn v		`thenM` \ name ->
+    returnM (HsIPVar name, emptyFVs)
 
 rnExpr (HsLit lit) 
-  = litFVs lit		`thenM` \ fvs -> 
-    returnM (HsLit lit, fvs)
+  = rnLit lit		`thenM_`
+    returnM (HsLit lit, emptyFVs)
 
 rnExpr (HsOverLit lit) 
   = rnOverLit lit		`thenM` \ (lit', fvs) ->
@@ -192,125 +189,96 @@ rnExpr (HsLam match)
     returnM (HsLam match', fvMatch)
 
 rnExpr (HsApp fun arg)
-  = rnExpr fun		`thenM` \ (fun',fvFun) ->
-    rnExpr arg		`thenM` \ (arg',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				`thenM` \ (e1', fv_e1) ->
-    rnExpr e2				`thenM` \ (e2', fv_e2) ->
-    rnExpr op				`thenM` \ (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				`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 -> 
+	-- 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 -> 
 
     returnM (final_e,
 	      fv_e1 `plusFV` fv_op `plusFV` fv_e2)
 
 rnExpr (NegApp e _)
-  = rnExpr e			`thenM` \ (e', fv_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 		`thenM` \ (e', fvs_e) ->
+  = rnLExpr e 		`thenM` \ (e', fvs_e) ->
     returnM (HsPar e', fvs_e)
 
 -- Template Haskell extensions
-#ifdef GHCI
-rnExpr (HsBracket br_body loc)
-  = addSrcLoc loc			$
-    checkGHCI (thErr "bracket")		`thenM_`
-    rnBracket br_body			`thenM` \ (body', fvs_e) ->
-    returnM (HsBracket body' loc, fvs_e `addOneFV` qTyConName)
-	-- We use the Q tycon as a proxy to haul in all the smart
-	-- constructors; see the hack in RnIfaces
-
-rnExpr (HsSplice n e loc)
-  = addSrcLoc loc			$
-    checkGHCI (thErr "splice")		`thenM_`
-    newLocalsRn [(n,loc)]		`thenM` \ [n'] ->
-    rnExpr e 				`thenM` \ (e', fvs_e) ->
-    returnM (HsSplice n' e' loc, fvs_e)    
-
-rnExpr (HsReify (Reify flavour name))
-  = checkGHCI (thErr "reify")		`thenM_`
-    lookupGlobalOccRn name		`thenM` \ name' ->
-	-- For now, we can only reify top-level things
-    returnM (HsReify (Reify flavour name'), mkFVs [name', qTyConName])
-	-- The qTyCon brutally pulls in all the meta stuff
-#endif
+-- 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	 				`thenM` \ (expr', fvs_expr) ->
-    rnExpr op	 				`thenM` \ (op', fvs_op) ->
+  = 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	 				`thenM` \ (op',   fvs_op) ->
-    rnExpr expr	 				`thenM` \ (expr', fvs_expr) ->
+  = 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 (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 (HsCoreAnn ann expr)
+  = rnLExpr expr `thenM` \ (expr', fvs_expr) ->
+    returnM (HsCoreAnn ann expr', fvs_expr)
 
 rnExpr (HsSCC lbl expr)
-  = rnExpr expr	 	`thenM` \ (expr', fvs_expr) ->
+  = rnLExpr expr	 	`thenM` \ (expr', fvs_expr) ->
     returnM (HsSCC lbl expr', fvs_expr)
 
-rnExpr (HsCase expr ms src_loc)
-  = addSrcLoc src_loc $
-    rnExpr expr		 		`thenM` \ (new_expr, e_fvs) ->
+rnExpr (HsCase expr ms)
+  = rnLExpr 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)
+    returnM (HsCase new_expr new_ms, e_fvs `plusFV` ms_fvs)
 
 rnExpr (HsLet binds expr)
-  = rnBindsAndThen binds	$ \ binds' ->
-    rnExpr expr			 `thenM` \ (expr',fvExpr) ->
+  = rnBindGroupsAndThen binds		$ \ binds' ->
+    rnLExpr 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) ->
+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 {
-	ResultStmt _ _ -> returnM () ;
-	_              -> addErr (doStmtListErr do_or_lc e)
+	L _ (ResultStmt _) -> returnM () ;
+	other              -> addLocErr other (doStmtListErr do_or_lc)
     }					`thenM_`
 
 	-- Generate the rebindable syntax for the monad
-    mapAndUnzipM lookupSyntaxName 
-	 (syntax_names do_or_lc)	`thenM` \ (monad_names', monad_fvs) ->
+    lookupSyntaxNames syntax_names	`thenM` \ (syntax_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)
+    returnM (HsDo do_or_lc stmts' syntax_names' placeHolderType, fvs `plusFV` 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   = []
+    syntax_names = case do_or_lc of
+			DoExpr  -> monadNames
+			MDoExpr -> monadNames ++ [mfixName]
+			other   -> []
 
 rnExpr (ExplicitList _ exps)
   = rnExprs exps		 	`thenM` \ (exps', fvs) ->
@@ -318,38 +286,38 @@ rnExpr (ExplicitList _ exps)
 
 rnExpr (ExplicitPArr _ exps)
   = rnExprs exps		 	`thenM` \ (exps', fvs) ->
-    returnM  (ExplicitPArr placeHolderType exps', 
-	       fvs `addOneFV` toPName `addOneFV` parrTyCon_name)
+    returnM  (ExplicitPArr placeHolderType exps', fvs)
 
-rnExpr (ExplicitTuple exps boxity)
-  = rnExprs exps	 			`thenM` \ (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 boxity (length exps)
+    tup_size   = length exps
+    tycon_name = tupleTyCon_name boxity tup_size
 
 rnExpr (RecordCon con_id rbinds)
-  = lookupOccRn con_id 			`thenM` \ conname ->
+  = lookupLocatedOccRn con_id		`thenM` \ conname ->
     rnRbinds "construction" rbinds	`thenM` \ (rbinds', fvRbinds) ->
-    returnM (RecordCon conname rbinds', fvRbinds `addOneFV` conname)
+    returnM (RecordCon conname rbinds', fvRbinds `addOneFV` unLoc conname)
 
 rnExpr (RecordUpd expr rbinds)
-  = rnExpr expr			`thenM` \ (expr', fvExpr) ->
+  = rnLExpr expr			`thenM` \ (expr', fvExpr) ->
     rnRbinds "update" rbinds	`thenM` \ (rbinds', fvRbinds) ->
     returnM (RecordUpd expr' rbinds', fvExpr `plusFV` fvRbinds)
 
 rnExpr (ExprWithTySig expr pty)
-  = rnExpr expr			`thenM` \ (expr', fvExpr) ->
+  = 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 src_loc)
-  = 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 (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) -> 
@@ -359,12 +327,11 @@ rnExpr (HsType a)
 
 rnExpr (ArithSeqIn seq)
   = rnArithSeq seq	 `thenM` \ (new_seq, fvs) ->
-    returnM (ArithSeqIn new_seq, fvs `addOneFV` enumClassName)
+    returnM (ArithSeqIn new_seq, fvs)
 
 rnExpr (PArrSeqIn seq)
   = rnArithSeq seq	 `thenM` \ (new_seq, fvs) ->
-    returnM (PArrSeqIn new_seq, 
-	     fvs `plusFV` mkFVs [enumFromToPName, enumFromThenToPName])
+    returnM (PArrSeqIn new_seq, fvs)
 \end{code}
 
 These three are pattern syntax appearing in expressions.
@@ -384,29 +351,252 @@ rnExpr e@(ELazyPat _) = addErr (patSynErr e)	`thenM_`
 
 %************************************************************************
 %*									*
+	Arrow notation
+%*									*
+%************************************************************************
+
+\begin{code}
+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
+    (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)
+
+convertOpFormsCmd (HsCase exp matches)
+  = HsCase exp (map 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
+
+convertOpFormsMatch = fmap convert
+ where convert (Match pat mty grhss)
+	  = Match pat mty (convertOpFormsGRHSs grhss)
+
+convertOpFormsGRHSs (GRHSs grhss binds ty)
+  = GRHSs (map convertOpFormsGRHS grhss) binds ty
+
+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)
+  = plusFVs (map 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 (L _ (Match pats sig_ty grhss)) = methodNamesGRHSs grhss
+
+-------------------------------------------------
+methodNamesGRHSs (GRHSs grhss binds ty) = 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)
- = rnExpr expr 	`thenM` \ (expr', fvExpr) ->
+ = rnLExpr expr 	`thenM` \ (expr', fvExpr) ->
    returnM (From expr', fvExpr)
 
 rnArithSeq (FromThen expr1 expr2)
- = rnExpr expr1 	`thenM` \ (expr1', fvExpr1) ->
-   rnExpr expr2	`thenM` \ (expr2', fvExpr2) ->
+ = rnLExpr expr1 	`thenM` \ (expr1', fvExpr1) ->
+   rnLExpr 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) ->
+ = rnLExpr expr1	`thenM` \ (expr1', fvExpr1) ->
+   rnLExpr 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) ->
+ = 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}
@@ -424,14 +614,14 @@ rnRbinds str rbinds
     mapFvRn rn_rbind rbinds		`thenM` \ (rbinds', fvRbind) ->
     returnM (rbinds', fvRbind)
   where
-    (_, dup_fields) = removeDups compare [ f | (f,_) <- rbinds ]
+    (_, dup_fields) = removeDups cmpLocated [ f | (f,_) <- rbinds ]
 
-    field_dup_err dups = addErr (dupFieldErr str dups)
+    field_dup_err dups = mappM_ (\f -> addLocErr f (dupFieldErr str)) dups
 
     rn_rbind (field, expr)
-      = lookupGlobalOccRn field	`thenM` \ fieldname ->
-	rnExpr expr		`thenM` \ (expr', fvExpr) ->
-	returnM ((fieldname, expr'), fvExpr `addOneFV` fieldname)
+      = lookupLocatedGlobalOccRn field	`thenM` \ fieldname ->
+	rnLExpr expr			`thenM` \ (expr', fvExpr) ->
+	returnM ((fieldname, expr'), fvExpr `addOneFV` unLoc fieldname)
 \end{code}
 
 %************************************************************************
@@ -441,9 +631,11 @@ rnRbinds str rbinds
 %************************************************************************
 
 \begin{code}
-rnBracket (ExpBr e) = rnExpr e		`thenM` \ (e', fvs) ->
+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) = rnPat p		`thenM` \ (p', 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)
@@ -453,12 +645,19 @@ 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 }) $
+    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', fvs) ->
+    rnSrcDecls group	`thenM` \ (tcg_env, group') ->
 	-- Discard the tcg_env; it contains only extra info about fixity
-
-    returnM (DecBr group', fvs)
+    let 
+	dus = tcg_dus tcg_env 
+    in
+    returnM (DecBr group', allUses dus)
 \end{code}
 
 %************************************************************************
@@ -468,108 +667,139 @@ rnBracket (DecBr group)
 %************************************************************************
 
 \begin{code}
-rnStmts :: HsStmtContext Name -> [RdrNameStmt] -> RnM ([RenamedStmt], FreeVars)
+rnStmts :: HsStmtContext Name -> [LStmt RdrName] -> RnM ([LStmt Name], FreeVars)
 
-rnStmts MDoExpr stmts = rnMDoStmts         stmts
-rnStmts ctxt   stmts  = rnNormalStmts ctxt stmts
+rnStmts MDoExpr = rnMDoStmts
+rnStmts ctxt    = rnNormalStmts ctxt
 
-rnNormalStmts :: HsStmtContext Name -> [RdrNameStmt] -> RnM ([RenamedStmt], FreeVars)	
+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 (ExprStmt expr _ src_loc : stmts)
-  = addSrcLoc src_loc 		$
-    rnExpr expr			`thenM` \ (expr', fv_expr) ->
+rnNormalStmts ctxt (L loc (ExprStmt expr _) : stmts)
+  = rnLExpr expr		        `thenM` \ (expr', fv_expr) ->
     rnNormalStmts ctxt stmts	`thenM` \ (stmts', fvs) ->
-    returnM (ExprStmt expr' placeHolderType src_loc : stmts',
+    returnM (L loc (ExprStmt expr' placeHolderType) : 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 [L loc (ResultStmt expr)]
+  = rnLExpr expr		`thenM` \ (expr', fv_expr) ->
+    returnM ([L loc (ResultStmt expr')], fv_expr)
 
-rnNormalStmts ctxt (BindStmt pat expr src_loc : stmts) 
-  = addSrcLoc src_loc 			$
-    rnExpr expr				`thenM` \ (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
 
-    rnPatsAndThen (StmtCtxt ctxt) [pat]	$ \ [pat'] ->
-    rnNormalStmts ctxt stmts		`thenM` \ (stmts', fvs) ->
-    returnM (BindStmt pat' expr' src_loc : stmts',
+    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 (LetStmt binds : stmts)
+rnNormalStmts ctxt (L loc (LetStmt binds) : stmts)
   = checkErr (ok ctxt binds) (badIpBinds binds)	`thenM_`
-    rnBindsAndThen binds			( \ binds' ->
+    rnBindGroupsAndThen binds			( \ binds' ->
     rnNormalStmts ctxt stmts			`thenM` \ (stmts', fvs) ->
-    returnM (LetStmt binds' : 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 _) (IPBinds _ _) = False	
-    ok _	       _	     = True
+    ok (ParStmtCtxt _) binds = not (any is_ip_bind binds)
+    ok _	       _     = True
+
+    is_ip_bind (HsIPBinds _) = True
+    is_ip_bind _	     = False
 
-rnNormalStmts ctxt (ParStmt stmtss : stmts)
-  = mapFvRn (rnNormalStmts (ParStmtCtxt ctxt)) stmtss	`thenM` \ (stmtss', fv_stmtss) ->
+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 = map collectStmtsBinders stmtss'
+	bndrss :: [[Name]]	-- NB: Name, not RdrName
+	bndrss = map (map unLoc . collectStmtsBinders) stmtss'
+	(bndrs, dups) = removeDups cmpByOcc (concat bndrss)
     in
-    foldlM checkBndrs [] bndrss		`thenM` \ new_binders ->
-    bindLocalNamesFV new_binders	$
+    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) ->
-    returnM (ParStmtOut (bndrss `zip` stmtss') : stmts', 
+
+	-- 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
-    checkBndrs all_bndrs bndrs
-	  = checkErr (null common) (err (head common)) `thenM_`
-	    returnM (bndrs ++ all_bndrs)
-	where
-	  common = intersectBy eqOcc all_bndrs bndrs
+    rn_branch (stmts, _) = rnNormalStmts (ParStmtCtxt ctxt) stmts
 
-    eqOcc n1 n2 = nameOccName n1 == nameOccName n2
-    err v = ptext SLIT("Duplicate binding in parallel list comprehension for:")
-	    <+> quotes (ppr v)
+    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 stmts = pprPanic "rnNormalStmts" (ppr stmts)
+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{Precedence Parsing}
+\subsubsection{mdo expressions}
 %*									*
 %************************************************************************
 
 \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 
+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
-		[RenamedStmt])
+		      stmts)	-- Either Stmt or [Stmt]
+
 
 ----------------------------------------------------
-rnMDoStmts :: [RdrNameStmt] -> RnM ([RenamedStmt], FreeVars)
+rnMDoStmts :: [LStmt RdrName] -> RnM ([LStmt Name], FreeVars)
 rnMDoStmts stmts
   = 	-- Step1: bring all the binders of the mdo into scope
-    bindLocalsRn doc (collectStmtsBinders stmts)	$ \ _ ->
+	-- 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
-    mappM rn_mdo_stmt stmts				`thenM` \ segs ->
+	-- 	   (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
@@ -593,42 +823,52 @@ rnMDoStmts stmts
   where
     doc = text "In a mdo-expression"
 
+
 ----------------------------------------------------
-rn_mdo_stmt :: RdrNameStmt -> RnM Segment
+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_mdo_stmt (ExprStmt expr _ src_loc)
-  = addSrcLoc src_loc (rnExpr expr)	`thenM` \ (expr', fvs) ->
-    returnM (emptyNameSet, fvs, emptyNameSet,
-	     [ExprStmt expr' placeHolderType src_loc])
+rn_rec_stmt (L loc (ExprStmt expr _))
+  = rnLExpr expr 		`thenM` \ (expr', fvs) ->
+    returnM [(emptyNameSet, fvs, emptyNameSet,
+	      L loc (ExprStmt expr' placeHolderType))]
 
-rn_mdo_stmt (ResultStmt expr src_loc)
-  = addSrcLoc src_loc (rnExpr expr)	`thenM` \ (expr', fvs) ->
-    returnM (emptyNameSet, fvs, emptyNameSet,
-	     [ResultStmt expr' src_loc])
+rn_rec_stmt (L loc (ResultStmt expr))
+  = rnLExpr expr			`thenM` \ (expr', fvs) ->
+    returnM [(emptyNameSet, fvs, emptyNameSet,
+	      L loc (ResultStmt expr'))]
 
-rn_mdo_stmt (BindStmt pat expr src_loc)
-  = addSrcLoc src_loc 	$
-    rnExpr expr		`thenM` \ (expr', fv_expr) ->
-    rnPat pat		`thenM` \ (pat', fv_pat) ->
+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,
-	     [BindStmt pat' expr' src_loc])
+    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_mdo_stmt (LetStmt binds)
-  = rnBinds binds		`thenM` \ (binds', fv_binds) ->
-    returnM (mkNameSet (collectHsBinders binds'), 
-	     fv_binds, emptyNameSet, [LetStmt binds'])
+rn_rec_stmt (L loc (RecStmt stmts _ _ _))	-- Flatten Rec inside Rec
+  = rn_rec_stmts stmts
 
-rn_mdo_stmt stmt@(ParStmt _)	-- Syntactically illegal in mdo
-  = pprPanic "rn_mdo_stmt" (ppr stmt)
+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] -> [Segment]
+
+---------------------------------------------
+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
@@ -636,12 +876,12 @@ addFwdRefs :: [Segment] -> [Segment]
 addFwdRefs pairs 
   = fst (foldr mk_seg ([], emptyNameSet) pairs)
   where
-    mk_seg (defs, uses, fwds, stmts) (segs, seg_defs)
+    mk_seg (defs, uses, fwds, stmts) (segs, later_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)
+	  all_defs = later_defs `unionNameSets` defs
+	  new_fwds = fwds `unionNameSets` (uses `intersectNameSet` later_defs)
 		-- Add the downstream fwd refs here
 
 ----------------------------------------------------
@@ -679,10 +919,10 @@ addFwdRefs pairs
 --		q <- x ; z <- y } ; 
 -- 	  r <- x }
 
-glomSegments :: [Segment] -> [Segment]
+glomSegments :: [Segment (LStmt Name)] -> [Segment [LStmt Name]]
 
-glomSegments [seg] = [seg]
-glomSegments ((defs,uses,fwds,stmts) : segs)
+glomSegments [] = []
+glomSegments ((defs,uses,fwds,stmt) : segs)
 	-- Actually stmts will always be a singleton
   = (seg_defs, seg_uses, seg_fwds, seg_stmts)  : others
   where
@@ -693,12 +933,12 @@ glomSegments ((defs,uses,fwds,stmts) : segs)
     seg_defs  = plusFVs ds `plusFV` defs
     seg_uses  = plusFVs us `plusFV` uses
     seg_fwds  = plusFVs fs `plusFV` fwds
-    seg_stmts = stmts ++ concat ss
+    seg_stmts = stmt : concat ss
 
     grab :: NameSet	 	-- The client
-	 -> [Segment]
-	 -> ([Segment],		-- Needed by the 'client'
-	     [Segment])		-- Not needed by 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)
@@ -708,7 +948,7 @@ glomSegments ((defs,uses,fwds,stmts) : segs)
 
 
 ----------------------------------------------------
-segsToStmts :: [Segment] -> ([RenamedStmt], FreeVars)
+segsToStmts :: [Segment [LStmt Name]] -> ([LStmt Name], FreeVars)
 
 segsToStmts [] = ([], emptyFVs)
 segsToStmts ((defs, uses, fwds, ss) : segs)
@@ -716,13 +956,12 @@ segsToStmts ((defs, uses, fwds, ss) : segs)
   where
     (later_stmts, later_uses) = segsToStmts segs
     new_stmt | non_rec	 = head ss
-	     | otherwise = RecStmt rec_names ss []
+	     | otherwise = L (getLoc (head ss)) $ 
+			   RecStmt ss (nameSetToList used_later) (nameSetToList fwds) []
 	     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
+	       non_rec    = isSingleton ss && isEmptyNameSet fwds
+	       used_later = defs `intersectNameSet` later_uses
+				-- The ones needed after the RecStmt
 \end{code}
 
 %************************************************************************
@@ -742,41 +981,43 @@ operator appications left-associatively, EXCEPT negation, which
 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)
-	  -> RnM 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
   = addErr (precParseErr (ppr_op op1,fix1) (ppr_op op2,fix2))	`thenM_`
     returnM (OpApp e1 op2 fix2 e2)
 
   | associate_right
   = mkOpAppRn e12 op2 fix2 e2		`thenM` \ new_e ->
-    returnM (OpApp e11 op1 fix1 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_name) op2 fix2 e2
+mkOpAppRn e1@(L _ (NegApp neg_arg neg_name)) op2 fix2 e2
   | nofix_error
   = 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	`thenM` \ new_e ->
-    returnM (NegApp new_e neg_name)
+    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 _)	-- NegApp can occur on the right
+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)
@@ -786,7 +1027,7 @@ mkOpAppRn e1 op1 fix1 e2@(NegApp neg_arg _)	-- NegApp can occur on the right
 ---------------------------
 --	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
     )
     returnM (OpApp e1 op fix e2)
@@ -802,38 +1043,33 @@ right_op_ok fix1 other
   = True
 
 -- Parser initially makes negation bind more tightly than any other operator
+-- And "deriving" code should respect this (use HsPar if not)
+mkNegAppRn :: LHsExpr id -> SyntaxName -> RnM (HsExpr id)
 mkNegAppRn neg_arg neg_name
-  = 
-#ifdef DEBUG
-    getModeRn			`thenM` \ mode ->
-    ASSERT( not_op_app mode neg_arg )
-#endif
+  = ASSERT( not_op_app (unLoc neg_arg) )
     returnM (NegApp neg_arg neg_name)
 
-not_op_app SourceMode (OpApp _ _ _ _) = False
-not_op_app mode other	 	      = True
+not_op_app (OpApp _ _ _ _) = False
+not_op_app other	   = True
 \end{code}
 
 \begin{code}
-checkPrecMatch :: Bool -> Name -> RenamedMatch -> RnM ()
+checkPrecMatch :: Bool -> Name -> LMatch Name -> RnM ()
 
 checkPrecMatch False fn match
   = returnM ()
 
-checkPrecMatch True op (Match (p1:p2:_) _ _)
+checkPrecMatch True op (L _ (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
+  = 	-- See comments with rnExpr (OpApp ...) about "deriving"
+    checkPrec op (unLoc p1) False	`thenM_`
+    checkPrec op (unLoc 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) ->
+  = 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 &&
@@ -853,13 +1089,15 @@ checkPrec op pat right
 -- 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 arg of
+  = case unLoc arg of
 	OpApp _ op fix _ -> go_for_it (ppr_op op)     fix
 	NegApp _ _	 -> go_for_it pp_prefix_minus negateFixity
 	other		 -> returnM ()
   where
-    HsVar op_name = op
+    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
@@ -876,15 +1114,15 @@ checkSectionPrec direction section op arg
 %************************************************************************
 
 \begin{code}
-mkAssertErrorExpr :: RnM (RenamedHsExpr, FreeVars)
+mkAssertErrorExpr :: RnM (HsExpr Name, FreeVars)
 -- Return an expression for (assertError "Foo.hs:27")
 mkAssertErrorExpr
-  = getSrcLocM    			`thenM` \ sloc ->
+  = getSrcSpanM    			`thenM` \ sloc ->
     let
-	expr = HsApp (HsVar assertErrorName) (HsLit msg)
+	expr = HsApp (L sloc (HsVar assertErrorName)) (L sloc (HsLit msg))
 	msg  = HsStringPrim (mkFastString (stringToUtf8 (showSDoc (ppr sloc))))
     in
-    returnM (expr, unitFV assertErrorName)
+    returnM (expr, emptyFVs)
 \end{code}
 
 %************************************************************************
@@ -914,9 +1152,16 @@ doStmtListErr do_or_lc e
 			MDoExpr -> "mdo"
 			other   -> "do"
 
-thErr what
-  = ptext SLIT("Template Haskell") <+> text what <+>  
-    ptext SLIT("illegal in a stage-1 compiler") 
+#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