X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=ghc%2Fcompiler%2Frename%2FRnExpr.lhs;h=eb92cd363e1d11c43baaef28e495d34a8104676b;hb=df65fd0b7646ffa17ed553289a4cd0e806bef8b9;hp=04db620b9993878ada476a8fb150327962adf771;hpb=7b0181919416d8f04324575b7e17031ca692f5b0;p=ghc-hetmet.git

diff --git a/ghc/compiler/rename/RnExpr.lhs b/ghc/compiler/rename/RnExpr.lhs
index 04db620..eb92cd3 100644
--- a/ghc/compiler/rename/RnExpr.lhs
+++ b/ghc/compiler/rename/RnExpr.lhs
@@ -1,37 +1,55 @@
 %
-% (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 @Qual@ 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, rnPat, rnExpr, rnExprs, rnStmt,
+	checkPrecMatch
    ) where
 
-import Ubiq
-import RnLoop		-- break the RnPass4/RnExpr4/RnBinds4 loops
+#include "HsVersions.h"
+
+import {-# SOURCE #-} RnBinds  ( rnBinds ) 
+import {-# SOURCE #-} RnSource ( rnHsTypeFVs )
 
 import HsSyn
 import RdrHsSyn
 import RnHsSyn
 import RnMonad
-
-import ErrUtils		( addErrLoc )
-import Name		( isLocallyDefinedName, pprOp, Name, RdrName )
-import Pretty
-import UniqFM		( lookupUFM )
-import UniqSet		( emptyUniqSet, unitUniqSet,
-			  unionUniqSets, unionManyUniqSets,
-			  UniqSet(..) )
-import Util		( Ord3(..), panic )
+import RnEnv
+import RnHiFiles	( lookupFixityRn )
+import CmdLineOpts	( DynFlag(..), opt_IgnoreAsserts )
+import Literal		( inIntRange, inCharRange )
+import BasicTypes	( Fixity(..), FixityDirection(..), defaultFixity, negateFixity )
+import PrelNames	( hasKey, assertIdKey, minusName, negateName, fromIntegerName,
+			  eqClass_RDR, foldr_RDR, build_RDR, eqString_RDR,
+			  cCallableClass_RDR, cReturnableClass_RDR, 
+			  monadClass_RDR, enumClass_RDR, ordClass_RDR,
+			  ratioDataCon_RDR, assertErr_RDR,
+			  ioDataCon_RDR, plusInteger_RDR, timesInteger_RDR,
+			  fromInteger_RDR, fromRational_RDR,
+			)
+import TysPrim		( charPrimTyCon, addrPrimTyCon, intPrimTyCon, 
+			  floatPrimTyCon, doublePrimTyCon
+			)
+import TysWiredIn	( intTyCon )
+import Name		( NamedThing(..), mkSysLocalName, nameSrcLoc )
+import NameSet
+import UniqFM		( isNullUFM )
+import FiniteMap	( elemFM )
+import UniqSet		( emptyUniqSet )
+import List		( intersectBy )
+import ListSetOps	( unionLists, removeDups )
+import Maybes		( maybeToBool )
+import Outputable
 \end{code}
 
 
@@ -42,61 +60,95 @@ import Util		( Ord3(..), panic )
 *********************************************************
 
 \begin{code}
-rnPat :: RdrNamePat -> RnM_Fixes s RenamedPat
+rnPat :: RdrNamePat -> RnMS (RenamedPat, FreeVars)
 
-rnPat WildPatIn = returnRn WildPatIn
+rnPat WildPatIn = returnRn (WildPatIn, emptyFVs)
 
 rnPat (VarPatIn name)
-  = lookupValue name	`thenRn` \ vname ->
-    returnRn (VarPatIn vname)
-
-rnPat (LitPatIn n) = returnRn (LitPatIn n)
+  = lookupBndrRn  name			`thenRn` \ vname ->
+    returnRn (VarPatIn vname, emptyFVs)
+
+rnPat (SigPatIn pat ty)
+  = doptRn Opt_GlasgowExts `thenRn` \ glaExts ->
+    
+    if glaExts
+    then rnPat pat		`thenRn` \ (pat', fvs1) ->
+         rnHsTypeFVs doc ty	`thenRn` \ (ty',  fvs2) ->
+         returnRn (SigPatIn pat' ty', fvs1 `plusFV` fvs2)
+
+    else addErrRn (patSigErr ty)	`thenRn_`
+         rnPat pat
+  where
+    doc = text "a pattern type-signature"
+    
+rnPat (LitPatIn s@(HsString _)) 
+  = lookupOrigName eqString_RDR		`thenRn` \ eq ->
+    returnRn (LitPatIn s, unitFV eq)
+
+rnPat (LitPatIn lit) 
+  = litFVs lit		`thenRn` \ fvs ->
+    returnRn (LitPatIn lit, fvs) 
+
+rnPat (NPatIn lit) 
+  = rnOverLit lit			`thenRn` \ (lit', fvs1) ->
+    lookupOrigName eqClass_RDR		`thenRn` \ eq   ->	-- Needed to find equality on pattern
+    returnRn (NPatIn lit', fvs1 `addOneFV` eq)
+
+rnPat (NPlusKPatIn name lit)
+  = rnOverLit lit			`thenRn` \ (lit', fvs) ->
+    lookupOrigName ordClass_RDR		`thenRn` \ ord ->
+    lookupBndrRn name			`thenRn` \ name' ->
+    returnRn (NPlusKPatIn name' lit', fvs `addOneFV` ord `addOneFV` minusName)
 
 rnPat (LazyPatIn pat)
-  = rnPat pat		`thenRn` \ pat' ->
-    returnRn (LazyPatIn pat')
+  = rnPat pat		`thenRn` \ (pat', fvs) ->
+    returnRn (LazyPatIn pat', fvs)
 
 rnPat (AsPatIn name pat)
-  = rnPat pat	`thenRn` \ pat' ->
-    lookupValue name	`thenRn` \ vname ->
-    returnRn (AsPatIn vname pat')
-
-rnPat (ConPatIn name pats)
-  = lookupValue name	`thenRn` \ name' ->
-    mapRn rnPat pats  	`thenRn` \ patslist ->
-    returnRn (ConPatIn name' patslist)
-
-rnPat (ConOpPatIn pat1 name pat2)
-  = lookupValue name	`thenRn` \ name' ->
-    rnPat pat1		`thenRn` \ pat1' ->
-    rnPat pat2		`thenRn` \ pat2' ->
-    precParsePat (ConOpPatIn pat1' name' pat2')
-
-rnPat neg@(NegPatIn pat)
-  = getSrcLocRn		`thenRn` \ src_loc ->
-    addErrIfRn (not (is_lit pat)) (negPatErr neg src_loc)
-			`thenRn_`
-    rnPat pat		`thenRn` \ pat' ->
-    returnRn (NegPatIn pat')
-  where
-    is_lit (LitPatIn _) = True
-    is_lit _            = False
+  = rnPat pat		`thenRn` \ (pat', fvs) ->
+    lookupBndrRn name	`thenRn` \ vname ->
+    returnRn (AsPatIn vname pat', fvs)
+
+rnPat (ConPatIn con pats)
+  = lookupOccRn con		`thenRn` \ con' ->
+    mapFvRn rnPat pats  	`thenRn` \ (patslist, fvs) ->
+    returnRn (ConPatIn con' patslist, fvs `addOneFV` con')
+
+rnPat (ConOpPatIn pat1 con _ pat2)
+  = rnPat pat1		`thenRn` \ (pat1', fvs1) ->
+    lookupOccRn con	`thenRn` \ con' ->
+    rnPat pat2		`thenRn` \ (pat2', fvs2) ->
+
+    getModeRn		`thenRn` \ mode ->
+	-- See comments with rnExpr (OpApp ...)
+    (if isInterfaceMode mode
+	then returnRn (ConOpPatIn pat1' con' defaultFixity pat2')
+	else lookupFixityRn con'	`thenRn` \ fixity ->
+	     mkConOpPatRn pat1' con' fixity pat2'
+    )								`thenRn` \ pat' ->
+    returnRn (pat', fvs1 `plusFV` fvs2 `addOneFV` con')
 
 rnPat (ParPatIn pat)
-  = rnPat pat		`thenRn` \ pat' ->
-    returnRn (ParPatIn pat')
+  = rnPat pat		`thenRn` \ (pat', fvs) ->
+    returnRn (ParPatIn pat', fvs)
 
 rnPat (ListPatIn pats)
-  = mapRn rnPat pats 	`thenRn` \ patslist ->
-    returnRn (ListPatIn patslist)
+  = mapFvRn rnPat pats			`thenRn` \ (patslist, fvs) ->
+    returnRn (ListPatIn patslist, fvs `addOneFV` listTyCon_name)
 
-rnPat (TuplePatIn pats)
-  = mapRn rnPat pats 	`thenRn` \ patslist ->
-    returnRn (TuplePatIn patslist)
+rnPat (TuplePatIn pats boxed)
+  = mapFvRn rnPat pats					   `thenRn` \ (patslist, fvs) ->
+    returnRn (TuplePatIn patslist boxed, fvs `addOneFV` tycon_name)
+  where
+    tycon_name = tupleTyCon_name boxed (length pats)
 
 rnPat (RecPatIn con rpats)
-  = panic "rnPat:RecPatIn"
-
+  = lookupOccRn con 	`thenRn` \ con' ->
+    rnRpats rpats	`thenRn` \ (rpats', fvs) ->
+    returnRn (RecPatIn con' rpats', fvs `addOneFV` con')
+rnPat (TypePatIn name) =
+    (rnHsTypeFVs (text "type pattern") name) `thenRn` \ (name', fvs) ->
+    returnRn (TypePatIn name', fvs)
 \end{code}
 
 ************************************************************************
@@ -106,63 +158,86 @@ rnPat (RecPatIn con rpats)
 ************************************************************************
 
 \begin{code}
-rnMatch :: RdrNameMatch -> RnM_Fixes s (RenamedMatch, FreeVars)
-
-rnMatch match
-  = getSrcLocRn			`thenRn` \ src_loc ->
-    newLocalNames "variable in pattern"
-	 (binders `zip` repeat src_loc)	`thenRn` \ new_binders ->
-    extendSS2 new_binders (rnMatch_aux match)
-  where
-    binders = collect_binders match
-
-    collect_binders :: RdrNameMatch -> [RdrName]
+rnMatch :: RdrNameMatch -> RnMS (RenamedMatch, FreeVars)
 
-    collect_binders (GRHSMatch _) = []
-    collect_binders (PatMatch pat match)
-      = collectPatBinders pat ++ collect_binders match
+rnMatch match@(Match _ pats maybe_rhs_sig grhss)
+  = pushSrcLocRn (getMatchLoc match)	$
 
-rnMatch_aux (PatMatch pat match)
-  = rnPat pat		`thenRn` \ pat' ->
-    rnMatch_aux match	`thenRn` \ (match', fvMatch) ->
-    returnRn (PatMatch pat' match', fvMatch)
+	-- Find the universally quantified type variables
+	-- in the pattern type signatures
+    getLocalNameEnv			`thenRn` \ name_env ->
+    let
+	tyvars_in_sigs = rhs_sig_tyvars `unionLists` tyvars_in_pats
+	rhs_sig_tyvars = case maybe_rhs_sig of
+				Nothing -> []
+				Just ty -> extractHsTyRdrTyVars ty
+	tyvars_in_pats = extractPatsTyVars pats
+	forall_tyvars  = filter (not . (`elemFM` name_env)) tyvars_in_sigs
+	doc_sig        = text "a pattern type-signature"
+	doc_pats       = text "a pattern match"
+    in
+    bindNakedTyVarsFVRn doc_sig forall_tyvars	$ \ sig_tyvars ->
+
+	-- Note that we do a single bindLocalsRn for all the
+	-- matches together, so that we spot the repeated variable in
+	--	f x x = 1
+    bindLocalsFVRn doc_pats (collectPatsBinders pats) $ \ new_binders ->
+
+    mapFvRn rnPat pats			`thenRn` \ (pats', pat_fvs) ->
+    rnGRHSs grhss			`thenRn` \ (grhss', grhss_fvs) ->
+    doptRn Opt_GlasgowExts		`thenRn` \ opt_GlasgowExts ->
+    (case maybe_rhs_sig of
+	Nothing -> returnRn (Nothing, emptyFVs)
+	Just ty | opt_GlasgowExts -> rnHsTypeFVs doc_sig ty	`thenRn` \ (ty', ty_fvs) ->
+				     returnRn (Just ty', ty_fvs)
+		| otherwise	  -> addErrRn (patSigErr ty)	`thenRn_`
+				     returnRn (Nothing, emptyFVs)
+    )					`thenRn` \ (maybe_rhs_sig', ty_fvs) ->
 
-rnMatch_aux (GRHSMatch grhss_and_binds)
-  = rnGRHSsAndBinds grhss_and_binds `thenRn` \ (grhss_and_binds', fvs) ->
-    returnRn (GRHSMatch grhss_and_binds', fvs)
+    let
+	binder_set     = mkNameSet new_binders
+	unused_binders = nameSetToList (binder_set `minusNameSet` grhss_fvs)
+	all_fvs	       = grhss_fvs `plusFV` pat_fvs `plusFV` ty_fvs
+    in
+    warnUnusedMatches unused_binders		`thenRn_`
+    
+    returnRn (Match sig_tyvars pats' maybe_rhs_sig' grhss', all_fvs)
+	-- The bindLocals and bindTyVars will remove the bound FVs
 \end{code}
 
 %************************************************************************
 %*									*
-\subsubsection{Guarded right-hand sides (GRHSsAndBinds)}
+\subsubsection{Guarded right-hand sides (GRHSs)}
 %*									*
 %************************************************************************
 
 \begin{code}
-rnGRHSsAndBinds :: RdrNameGRHSsAndBinds -> RnM_Fixes s (RenamedGRHSsAndBinds, FreeVars)
-
-rnGRHSsAndBinds (GRHSsAndBindsIn grhss binds)
-  = rnBinds binds			`thenRn` \ (binds', fvBinds, scope) ->
-    extendSS2 scope (rnGRHSs grhss)	`thenRn` \ (grhss', fvGRHS) ->
-    returnRn (GRHSsAndBindsIn grhss' binds', fvBinds `unionUniqSets` fvGRHS)
+rnGRHSs :: RdrNameGRHSs -> RnMS (RenamedGRHSs, FreeVars)
+
+rnGRHSs (GRHSs grhss binds maybe_ty)
+  = ASSERT( not (maybeToBool maybe_ty) )
+    rnBinds binds		$ \ binds' ->
+    mapFvRn rnGRHS grhss	`thenRn` \ (grhss', fvGRHSs) ->
+    returnRn (GRHSs grhss' binds' Nothing, fvGRHSs)
+
+rnGRHS (GRHS guarded locn)
+  = doptRn Opt_GlasgowExts		`thenRn` \ opt_GlasgowExts ->
+    pushSrcLocRn locn $		    
+    (if not (opt_GlasgowExts || is_standard_guard guarded) then
+		addWarnRn (nonStdGuardErr guarded)
+     else
+		returnRn ()
+    )		`thenRn_`
+
+    rnStmts guarded	`thenRn` \ ((_, guarded'), fvs) ->
+    returnRn (GRHS guarded' locn, fvs)
   where
-    rnGRHSs [] = returnRn ([], emptyUniqSet)
-
-    rnGRHSs (grhs:grhss)
-      = rnGRHS  grhs   `thenRn` \ (grhs',  fvs) ->
-	rnGRHSs grhss  `thenRn` \ (grhss', fvss) ->
-	returnRn (grhs' : grhss', fvs `unionUniqSets` fvss)
-
-    rnGRHS (GRHS guard expr locn)
-      = pushSrcLocRn locn $		    
-	rnExpr guard	`thenRn` \ (guard', fvsg) ->
-	rnExpr expr	`thenRn` \ (expr',  fvse) ->
-	returnRn (GRHS guard' expr' locn, fvsg `unionUniqSets` fvse)
-
-    rnGRHS (OtherwiseGRHS expr locn)
-      = pushSrcLocRn locn $
-	rnExpr expr	`thenRn` \ (expr', fvs) ->
-	returnRn (OtherwiseGRHS expr' locn, fvs)
+	-- Standard Haskell 1.4 guards are just a single boolean
+	-- expression, rather than a list of qualifiers as in the
+	-- Glasgow extension
+    is_standard_guard [ExprStmt _ _]               = True
+    is_standard_guard [ExprStmt _ _, ExprStmt _ _] = True
+    is_standard_guard other	      		   = False
 \end{code}
 
 %************************************************************************
@@ -172,38 +247,51 @@ rnGRHSsAndBinds (GRHSsAndBindsIn grhss binds)
 %************************************************************************
 
 \begin{code}
-rnExprs :: [RdrNameHsExpr] -> RnM_Fixes s ([RenamedHsExpr], FreeVars)
-
-rnExprs [] = returnRn ([], emptyUniqSet)
+rnExprs :: [RdrNameHsExpr] -> RnMS ([RenamedHsExpr], FreeVars)
+rnExprs ls = rnExprs' ls emptyUniqSet
+ where
+  rnExprs' [] acc = returnRn ([], acc)
+  rnExprs' (expr:exprs) acc
+   = rnExpr expr 	        `thenRn` \ (expr', fvExpr) ->
+
+	-- Now we do a "seq" on the free vars because typically it's small
+	-- or empty, especially in very long lists of constants
+    let
+	acc' = acc `plusFV` fvExpr
+    in
+    (grubby_seqNameSet acc' rnExprs') exprs acc'	`thenRn` \ (exprs', fvExprs) ->
+    returnRn (expr':exprs', fvExprs)
 
-rnExprs (expr:exprs)
-  = rnExpr expr 	`thenRn` \ (expr', fvExpr) ->
-    rnExprs exprs	`thenRn` \ (exprs', fvExprs) ->
-    returnRn (expr':exprs', fvExpr `unionUniqSets` 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 RnName returned from the lookup, and make it part of the
-free-var set iff if it's a LocallyDefined RnName.
-
-ToDo: what about RnClassOps ???
-\end{itemize}
+Variables. We look up the variable and return the resulting name. 
 
 \begin{code}
-rnExpr :: RdrNameHsExpr -> RnM_Fixes s (RenamedHsExpr, FreeVars)
+rnExpr :: RdrNameHsExpr -> RnMS (RenamedHsExpr, FreeVars)
 
 rnExpr (HsVar v)
-  = lookupValue v	`thenRn` \ vname ->
-    returnRn (HsVar vname, fv_set vname)
-  where
-    fv_set vname@(RnName n)
-      | isLocallyDefinedName n = unitUniqSet vname
-      | otherwise	       = emptyUniqSet
+  = lookupOccRn v	`thenRn` \ name ->
+    if name `hasKey` assertIdKey then
+	-- We expand it to (GHCerr.assert__ location)
+        mkAssertExpr
+    else
+        -- The normal case
+       returnRn (HsVar name, unitFV name)
+
+rnExpr (HsIPVar v)
+  = newIPName v			`thenRn` \ name ->
+    returnRn (HsIPVar name, emptyFVs)
 
-rnExpr (HsLit lit)
-  = returnRn (HsLit lit, emptyUniqSet)
+rnExpr (HsLit lit) 
+  = litFVs lit		`thenRn` \ fvs -> 
+    returnRn (HsLit lit, fvs)
+
+rnExpr (HsOverLit lit) 
+  = rnOverLit lit		`thenRn` \ (lit', fvs) ->
+    returnRn (HsOverLit lit', fvs)
 
 rnExpr (HsLam match)
   = rnMatch match	`thenRn` \ (match', fvMatch) ->
@@ -212,90 +300,137 @@ rnExpr (HsLam match)
 rnExpr (HsApp fun arg)
   = rnExpr fun		`thenRn` \ (fun',fvFun) ->
     rnExpr arg		`thenRn` \ (arg',fvArg) ->
-    returnRn (HsApp fun' arg', fvFun `unionUniqSets` fvArg)
-
-rnExpr (OpApp e1 op e2)
-  = rnExpr e1		`thenRn` \ (e1', fvs_e1) ->
-    rnExpr op		`thenRn` \ (op', fvs_op) ->
-    rnExpr e2		`thenRn` \ (e2', fvs_e2) ->
-    precParseExpr (OpApp e1' op' e2') `thenRn` \ exp ->
-    returnRn (exp, (fvs_op `unionUniqSets` fvs_e1) `unionUniqSets` fvs_e2)
+    returnRn (HsApp fun' arg', fvFun `plusFV` fvArg)
+
+rnExpr (OpApp e1 op _ e2) 
+  = rnExpr e1				`thenRn` \ (e1', fv_e1) ->
+    rnExpr e2				`thenRn` \ (e2', fv_e2) ->
+    rnExpr op				`thenRn` \ (op'@(HsVar op_name), fv_op) ->
+
+	-- Deal with fixity
+	-- When renaming code synthesised from "deriving" declarations
+	-- we're in Interface mode, and we should ignore fixity; assume
+	-- that the deriving code generator got the association correct
+	-- Don't even look up the fixity when in interface mode
+    getModeRn				`thenRn` \ mode -> 
+    (if isInterfaceMode mode
+	then returnRn (OpApp e1' op' defaultFixity e2')
+	else lookupFixityRn op_name		`thenRn` \ fixity ->
+	     mkOpAppRn e1' op' fixity e2'
+    )					`thenRn` \ final_e -> 
+
+    returnRn (final_e,
+	      fv_e1 `plusFV` fv_op `plusFV` fv_e2)
 
 rnExpr (NegApp e)
-  = rnExpr e 		`thenRn` \ (e', fvs_e) ->
-    returnRn (NegApp e', fvs_e)
+  = rnExpr e			`thenRn` \ (e', fv_e) ->
+    mkNegAppRn e'		`thenRn` \ final_e ->
+    returnRn (final_e, fv_e `addOneFV` negateName)
 
 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 `unionUniqSets` fvs_expr)
-
-rnExpr (SectionR op expr)
-  = rnExpr op	 	`thenRn` \ (op',   fvs_op) ->
-    rnExpr expr	 	`thenRn` \ (expr', fvs_expr) ->
-    returnRn (SectionR op' expr', fvs_op `unionUniqSets` fvs_expr)
-
-rnExpr (CCall fun args may_gc is_casm fake_result_ty)
-  = rnExprs args	`thenRn` \ (args', fvs_args) ->
-    returnRn (CCall fun args' may_gc is_casm fake_result_ty, fvs_args)
-
-rnExpr (HsSCC label expr)
+rnExpr section@(SectionL expr op)
+  = rnExpr expr	 				`thenRn` \ (expr', fvs_expr) ->
+    rnExpr op	 				`thenRn` \ (op', fvs_op) ->
+    checkSectionPrec "left" section op' expr'	`thenRn_`
+    returnRn (SectionL expr' op', fvs_op `plusFV` fvs_expr)
+
+rnExpr section@(SectionR op expr)
+  = rnExpr op	 				`thenRn` \ (op',   fvs_op) ->
+    rnExpr expr	 				`thenRn` \ (expr', fvs_expr) ->
+    checkSectionPrec "right" section op' expr'	`thenRn_`
+    returnRn (SectionR op' expr', fvs_op `plusFV` fvs_expr)
+
+rnExpr (HsCCall fun args may_gc is_casm fake_result_ty)
+	-- Check out the comment on RnIfaces.getNonWiredDataDecl about ccalls
+  = lookupOrigNames [cCallableClass_RDR, 
+			  cReturnableClass_RDR, 
+			  ioDataCon_RDR]	`thenRn` \ implicit_fvs ->
+    rnExprs args				`thenRn` \ (args', fvs_args) ->
+    returnRn (HsCCall fun args' may_gc is_casm fake_result_ty, 
+	      fvs_args `plusFV` implicit_fvs)
+
+rnExpr (HsSCC lbl expr)
   = rnExpr expr	 	`thenRn` \ (expr', fvs_expr) ->
-    returnRn (HsSCC label expr', fvs_expr)
+    returnRn (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, unionManyUniqSets (e_fvs : ms_fvs))
+    mapFvRn rnMatch ms		`thenRn` \ (new_ms, ms_fvs) ->
+    returnRn (HsCase new_expr new_ms src_loc, e_fvs `plusFV` ms_fvs)
 
 rnExpr (HsLet binds expr)
-  = rnBinds binds		`thenRn` \ (binds', fvBinds, new_binders) ->
-    extendSS2 new_binders (rnExpr expr) `thenRn` \ (expr',fvExpr) ->
-    returnRn (HsLet binds' expr', fvBinds `unionUniqSets` fvExpr)
+  = rnBinds binds		$ \ binds' ->
+    rnExpr expr			 `thenRn` \ (expr',fvExpr) ->
+    returnRn (HsLet binds' expr', fvExpr)
+
+rnExpr (HsWith expr binds)
+  = rnExpr expr			`thenRn` \ (expr',fvExpr) ->
+    rnIPBinds binds		`thenRn` \ (binds',fvBinds) ->
+    returnRn (HsWith expr' binds', fvExpr `plusFV` fvBinds)
 
-rnExpr (HsDo stmts src_loc)
+rnExpr e@(HsDo do_or_lc stmts src_loc)
   = pushSrcLocRn src_loc $
-    rnStmts stmts		`thenRn` \ (stmts', fvStmts) ->
-    returnRn (HsDo stmts' src_loc, fvStmts)
+    lookupOrigNames implicit_rdr_names	`thenRn` \ implicit_fvs ->
+    rnStmts stmts			`thenRn` \ ((_, stmts'), fvs) ->
+	-- check the statement list ends in an expression
+    case last stmts' of {
+	ExprStmt _ _ -> returnRn () ;
+	_            -> addErrRn (doStmtListErr e)
+    }					`thenRn_`
+    returnRn (HsDo do_or_lc stmts' src_loc, fvs `plusFV` implicit_fvs)
+  where
+    implicit_rdr_names = [foldr_RDR, build_RDR, monadClass_RDR]
+	-- Monad stuff should not be necessary for a list comprehension
+	-- but the typechecker looks up the bind and return Ids anyway
+	-- Oh well.
 
-rnExpr (ListComp expr quals)
-  = rnQuals quals 		`thenRn` \ ((quals', qual_binders), fvQuals) ->
-    extendSS2 qual_binders (rnExpr expr) `thenRn` \ (expr', fvExpr) ->
-    returnRn (ListComp expr' quals', fvExpr `unionUniqSets` fvQuals)
 
 rnExpr (ExplicitList exps)
-  = rnExprs exps	 	`thenRn` \ (exps', fvs) ->
-    returnRn  (ExplicitList exps', fvs)
+  = rnExprs exps		 	`thenRn` \ (exps', fvs) ->
+    returnRn  (ExplicitList exps', fvs `addOneFV` listTyCon_name)
+
+rnExpr (ExplicitTuple exps boxity)
+  = rnExprs exps	 			`thenRn` \ (exps', fvs) ->
+    returnRn (ExplicitTuple exps' boxity, fvs `addOneFV` tycon_name)
+  where
+    tycon_name = tupleTyCon_name boxity (length exps)
 
-rnExpr (ExplicitTuple exps)
-  = rnExprs exps	 	`thenRn` \ (exps', fvExps) ->
-    returnRn (ExplicitTuple exps', fvExps)
+rnExpr (RecordCon con_id rbinds)
+  = lookupOccRn con_id 			`thenRn` \ conname ->
+    rnRbinds "construction" rbinds	`thenRn` \ (rbinds', fvRbinds) ->
+    returnRn (RecordCon conname rbinds', fvRbinds `addOneFV` conname)
 
-rnExpr (RecordCon con rbinds)
-  = panic "rnExpr:RecordCon"
-rnExpr (RecordUpd exp rbinds)
-  = panic "rnExpr:RecordUpd"
+rnExpr (RecordUpd expr rbinds)
+  = rnExpr expr			`thenRn` \ (expr', fvExpr) ->
+    rnRbinds "update" rbinds	`thenRn` \ (rbinds', fvRbinds) ->
+    returnRn (RecordUpd expr' rbinds', fvExpr `plusFV` fvRbinds)
 
 rnExpr (ExprWithTySig expr pty)
-  = rnExpr expr			 	`thenRn` \ (expr', fvExpr) ->
-    rnPolyType nullTyVarNamesEnv pty `thenRn` \ pty' ->
-    returnRn (ExprWithTySig expr' pty', fvExpr)
+  = rnExpr expr			 			   `thenRn` \ (expr', fvExpr) ->
+    rnHsTypeFVs (text "an expression type signature") pty  `thenRn` \ (pty', fvTy) ->
+    returnRn (ExprWithTySig expr' pty', fvExpr `plusFV` fvTy)
 
 rnExpr (HsIf p b1 b2 src_loc)
   = pushSrcLocRn src_loc $
     rnExpr p		`thenRn` \ (p', fvP) ->
     rnExpr b1		`thenRn` \ (b1', fvB1) ->
     rnExpr b2		`thenRn` \ (b2', fvB2) ->
-    returnRn (HsIf p' b1' b2' src_loc, unionManyUniqSets [fvP, fvB1, fvB2])
+    returnRn (HsIf p' b1' b2' src_loc, plusFVs [fvP, fvB1, fvB2])
+
+rnExpr (HsType a)
+  = rnHsTypeFVs doc a	`thenRn` \ (t, fvT) -> 
+    returnRn (HsType t, fvT)
+  where 
+    doc = text "renaming a type pattern"
 
 rnExpr (ArithSeqIn seq)
-  = rn_seq seq 		`thenRn` \ (new_seq, fvs) ->
-    returnRn (ArithSeqIn new_seq, fvs)
+  = lookupOrigName enumClass_RDR	`thenRn` \ enum ->
+    rn_seq seq	 			`thenRn` \ (new_seq, fvs) ->
+    returnRn (ArithSeqIn new_seq, fvs `addOneFV` enum)
   where
     rn_seq (From expr)
      = rnExpr expr 	`thenRn` \ (expr', fvExpr) ->
@@ -304,25 +439,93 @@ rnExpr (ArithSeqIn seq)
     rn_seq (FromThen expr1 expr2)
      = rnExpr expr1 	`thenRn` \ (expr1', fvExpr1) ->
        rnExpr expr2	`thenRn` \ (expr2', fvExpr2) ->
-       returnRn (FromThen expr1' expr2', fvExpr1 `unionUniqSets` fvExpr2)
+       returnRn (FromThen expr1' expr2', fvExpr1 `plusFV` fvExpr2)
 
     rn_seq (FromTo expr1 expr2)
      = rnExpr expr1	`thenRn` \ (expr1', fvExpr1) ->
        rnExpr expr2	`thenRn` \ (expr2', fvExpr2) ->
-       returnRn (FromTo expr1' expr2', fvExpr1 `unionUniqSets` fvExpr2)
+       returnRn (FromTo expr1' expr2', fvExpr1 `plusFV` fvExpr2)
 
     rn_seq (FromThenTo expr1 expr2 expr3)
      = rnExpr expr1	`thenRn` \ (expr1', fvExpr1) ->
        rnExpr expr2	`thenRn` \ (expr2', fvExpr2) ->
        rnExpr expr3	`thenRn` \ (expr3', fvExpr3) ->
        returnRn (FromThenTo expr1' expr2' expr3',
-		  unionManyUniqSets [fvExpr1, fvExpr2, fvExpr3])
+		  plusFVs [fvExpr1, fvExpr2, fvExpr3])
+\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 = addErrRn (patSynErr e)	`thenRn_`
+		    returnRn (EWildPat, emptyFVs)
+
+rnExpr e@(EAsPat _ _) = addErrRn (patSynErr e)	`thenRn_`
+		        returnRn (EWildPat, emptyFVs)
 
+rnExpr e@(ELazyPat _) = addErrRn (patSynErr e)	`thenRn_`
+		        returnRn (EWildPat, emptyFVs)
 \end{code}
 
+
+
 %************************************************************************
 %*									*
-\subsubsection{@Qual@s: in list comprehensions}
+\subsubsection{@Rbinds@s and @Rpats@s: in record expressions}
+%*									*
+%************************************************************************
+
+\begin{code}
+rnRbinds str rbinds 
+  = mapRn_ field_dup_err dup_fields	`thenRn_`
+    mapFvRn rn_rbind rbinds		`thenRn` \ (rbinds', fvRbind) ->
+    returnRn (rbinds', fvRbind)
+  where
+    (_, dup_fields) = removeDups compare [ f | (f,_,_) <- rbinds ]
+
+    field_dup_err dups = addErrRn (dupFieldErr str dups)
+
+    rn_rbind (field, expr, pun)
+      = lookupGlobalOccRn field	`thenRn` \ fieldname ->
+	rnExpr expr		`thenRn` \ (expr', fvExpr) ->
+	returnRn ((fieldname, expr', pun), fvExpr `addOneFV` fieldname)
+
+rnRpats rpats
+  = mapRn_ field_dup_err dup_fields 	`thenRn_`
+    mapFvRn rn_rpat rpats		`thenRn` \ (rpats', fvs) ->
+    returnRn (rpats', fvs)
+  where
+    (_, dup_fields) = removeDups compare [ f | (f,_,_) <- rpats ]
+
+    field_dup_err dups = addErrRn (dupFieldErr "pattern" dups)
+
+    rn_rpat (field, pat, pun)
+      = lookupGlobalOccRn field	`thenRn` \ fieldname ->
+	rnPat pat		`thenRn` \ (pat', fvs) ->
+	returnRn ((fieldname, pat', pun), fvs `addOneFV` fieldname)
+\end{code}
+
+%************************************************************************
+%*									*
+\subsubsection{@rnIPBinds@s: in implicit parameter bindings}		*
+%*									*
+%************************************************************************
+
+\begin{code}
+rnIPBinds [] = returnRn ([], emptyFVs)
+rnIPBinds ((n, expr) : binds)
+  = newIPName n			`thenRn` \ name ->
+    rnExpr expr			`thenRn` \ (expr',fvExpr) ->
+    rnIPBinds binds		`thenRn` \ (binds',fvBinds) ->
+    returnRn ((name, expr') : binds', fvExpr `plusFV` fvBinds)
+
+\end{code}
+
+%************************************************************************
+%*									*
+\subsubsection{@Stmt@s: in @do@ expressions}
 %*									*
 %************************************************************************
 
@@ -335,182 +538,388 @@ be @{r}@, and the free var set for the entire Quals will be @{r}@. This
 Quals.
 
 \begin{code}
-rnQuals :: [RdrNameQual]
-	 -> RnM_Fixes s (([RenamedQual],	-- renamed qualifiers
-		         [RnName]),		-- qualifiers' binders
-		         FreeVars)		-- free variables
-
-rnQuals [qual] 				-- must be at least one qual
-  = rnQual qual `thenRn` \ ((new_qual, bs), fvs) ->
-    returnRn (([new_qual], bs), fvs)
-
-rnQuals (qual: quals)
-  = rnQual qual				`thenRn` \ ((qual',  bs1), fvQuals1) ->
-    extendSS2 bs1 (rnQuals quals)	`thenRn` \ ((quals', bs2), fvQuals2) ->
-    returnRn
-       ((qual' : quals', bs2 ++ bs1),	-- The ones on the right (bs2) shadow the
-					-- ones on the left (bs1)
-	fvQuals1 `unionUniqSets` fvQuals2)
-
-rnQual (GeneratorQual pat expr)
-  = rnExpr expr		 `thenRn` \ (expr', fvExpr) ->
-    let
-	binders = collectPatBinders pat
-    in
-    getSrcLocRn		 `thenRn` \ src_loc ->
-    newLocalNames "variable in list-comprehension-generator pattern"
-	 (binders `zip` repeat src_loc)	  `thenRn` \ new_binders ->
-    extendSS new_binders (rnPat pat) `thenRn` \ pat' ->
+rnStmts :: [RdrNameStmt]
+	-> RnMS (([Name], [RenamedStmt]), FreeVars)
 
-    returnRn ((GeneratorQual pat' expr', new_binders), fvExpr)
+rnStmts []
+  = returnRn (([], []), emptyFVs)
 
-rnQual (FilterQual expr)
-  = rnExpr expr	 `thenRn` \ (expr', fvs) ->
-    returnRn ((FilterQual expr', []), fvs)
+rnStmts (stmt:stmts)
+  = getLocalNameEnv 		`thenRn` \ name_env ->
+    rnStmt stmt				$ \ stmt' ->
+    rnStmts stmts			`thenRn` \ ((binders, stmts'), fvs) ->
+    returnRn ((binders, stmt' : stmts'), fvs)
+
+rnStmt :: RdrNameStmt
+       -> (RenamedStmt -> RnMS (([Name], a), FreeVars))
+       -> RnMS (([Name], a), FreeVars)
+-- The thing list of names returned is the list returned by the
+-- thing_inside, plus the binders of the arguments stmt
+
+-- Because of mutual recursion we have to pass in rnExpr.
+
+rnStmt (ParStmt stmtss) thing_inside
+  = mapFvRn rnStmts stmtss		`thenRn` \ (bndrstmtss, fv_stmtss) ->
+    let binderss = map fst bndrstmtss
+	checkBndrs all_bndrs bndrs
+	  = checkRn (null (intersectBy eqOcc all_bndrs bndrs)) err `thenRn_`
+	    returnRn (bndrs ++ all_bndrs)
+	eqOcc n1 n2 = nameOccName n1 == nameOccName n2
+	err = text "duplicate binding in parallel list comprehension"
+    in
+    foldlRn checkBndrs [] binderss	`thenRn` \ new_binders ->
+    bindLocalNamesFV new_binders	$
+    thing_inside (ParStmtOut bndrstmtss)`thenRn` \ ((rest_bndrs, result), fv_rest) ->
+    returnRn ((new_binders ++ rest_bndrs, result), fv_stmtss `plusFV` fv_rest)
 
-rnQual (LetQual binds)
-  = rnBinds binds	`thenRn` \ (binds', binds_fvs, new_binders) ->
-    returnRn ((LetQual binds', new_binders), binds_fvs)
-\end{code}
+rnStmt (BindStmt pat expr src_loc) thing_inside
+  = pushSrcLocRn src_loc $
+    rnExpr expr					`thenRn` \ (expr', fv_expr) ->
+    bindLocalsFVRn doc binders			$ \ new_binders ->
+    rnPat pat					`thenRn` \ (pat', fv_pat) ->
+    thing_inside (BindStmt pat' expr' src_loc)	`thenRn` \ ((rest_binders, result), fvs) ->
+    -- ZZ is shadowing handled correctly?
+    returnRn ((new_binders ++ rest_binders, result),
+	      fv_expr `plusFV` fvs `plusFV` fv_pat)
+  where
+    binders = collectPatBinders pat
+    doc = text "a pattern in do binding" 
 
+rnStmt (ExprStmt expr src_loc) thing_inside
+  = pushSrcLocRn src_loc $
+    rnExpr expr 				`thenRn` \ (expr', fv_expr) ->
+    thing_inside (ExprStmt expr' src_loc)	`thenRn` \ (result, fvs) ->
+    returnRn (result, fv_expr `plusFV` fvs)
+
+rnStmt (LetStmt binds) thing_inside
+  = rnBinds binds				$ \ binds' ->
+    let new_binders = collectHsBinders binds' in
+    thing_inside (LetStmt binds')    `thenRn` \ ((rest_binders, result), fvs) ->
+    returnRn ((new_binders ++ rest_binders, result), fvs )
+\end{code}
 
 %************************************************************************
 %*									*
-\subsubsection{@Stmt@s: in @do@ expressions}
+\subsubsection{Precedence Parsing}
 %*									*
 %************************************************************************
 
+@mkOpAppRn@ deals with operator fixities.  The argument expressions
+are assumed to be already correctly arranged.  It needs the fixities
+recorded in the OpApp nodes, because fixity info applies to the things
+the programmer actually wrote, so you can't find it out from the Name.
+
+Furthermore, the second argument is guaranteed not to be another
+operator application.  Why? Because the parser parses all
+operator appications left-associatively, EXCEPT negation, which
+we need to handle specially.
+
 \begin{code}
-rnStmts :: [RdrNameStmt] -> RnM_Fixes s ([RenamedStmt], FreeVars)
+mkOpAppRn :: RenamedHsExpr			-- Left operand; already rearranged
+	  -> RenamedHsExpr -> Fixity 		-- Operator and fixity
+	  -> RenamedHsExpr			-- Right operand (not an OpApp, but might
+						-- be a NegApp)
+	  -> RnMS RenamedHsExpr
+
+---------------------------
+-- (e11 `op1` e12) `op2` e2
+mkOpAppRn e1@(OpApp e11 op1 fix1 e12) op2 fix2 e2
+  | nofix_error
+  = addErrRn (precParseErr (ppr_op op1,fix1) (ppr_op op2,fix2))	`thenRn_`
+    returnRn (OpApp e1 op2 fix2 e2)
+
+  | associate_right
+  = mkOpAppRn e12 op2 fix2 e2		`thenRn` \ new_e ->
+    returnRn (OpApp e11 op1 fix1 new_e)
+  where
+    (nofix_error, associate_right) = compareFixity fix1 fix2
+
+---------------------------
+--	(- neg_arg) `op` e2
+mkOpAppRn e1@(NegApp neg_arg) op2 fix2 e2
+  | nofix_error
+  = addErrRn (precParseErr (pp_prefix_minus,negateFixity) (ppr_op op2,fix2))	`thenRn_`
+    returnRn (OpApp e1 op2 fix2 e2)
+
+  | associate_right
+  = mkOpAppRn neg_arg op2 fix2 e2	`thenRn` \ new_e ->
+    returnRn (NegApp new_e)
+  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
+  = addErrRn (precParseErr (ppr_op op1, fix1) (pp_prefix_minus, negateFixity))	`thenRn_`
+    returnRn (OpApp e1 op1 fix1 e2)
+  where
+    (_, associate_right) = compareFixity fix1 negateFixity
+
+---------------------------
+--	Default case
+mkOpAppRn e1 op fix e2 			-- Default case, no rearrangment
+  = ASSERT2( right_op_ok fix e2,
+	     ppr e1 $$ text "---" $$ ppr op $$ text "---" $$ ppr fix $$ text "---" $$ ppr e2
+    )
+    returnRn (OpApp e1 op fix e2)
+
+-- Parser left-associates everything, but 
+-- derived instances may have correctly-associated things to
+-- in the right operarand.  So we just check that the right operand is OK
+right_op_ok fix1 (OpApp _ _ fix2 _)
+  = not error_please && associate_right
+  where
+    (error_please, associate_right) = compareFixity fix1 fix2
+right_op_ok fix1 other
+  = True
 
-rnStmts [stmt@(ExprStmt _ _)]		-- last stmt must be ExprStmt
-  = rnStmt stmt				`thenRn` \ ((stmt',[]), fvStmt) ->
-    returnRn ([stmt'], fvStmt)
+-- Parser initially makes negation bind more tightly than any other operator
+mkNegAppRn neg_arg
+  = 
+#ifdef DEBUG
+    getModeRn			`thenRn` \ mode ->
+    ASSERT( not_op_app mode neg_arg )
+#endif
+    returnRn (NegApp neg_arg)
+
+not_op_app SourceMode (OpApp _ _ _ _) = False
+not_op_app mode other	 	      = True
+\end{code}
 
-rnStmts (stmt:stmts)
-  = rnStmt stmt				`thenRn` \ ((stmt',bs), fvStmt) ->
-    extendSS2 bs (rnStmts stmts)	`thenRn` \ (stmts',     fvStmts) ->
-    returnRn (stmt':stmts', fvStmt `unionUniqSets` fvStmts)
+\begin{code}
+mkConOpPatRn :: RenamedPat -> Name -> Fixity -> RenamedPat
+	     -> RnMS RenamedPat
 
+mkConOpPatRn p1@(ConOpPatIn p11 op1 fix1 p12) 
+	     op2 fix2 p2
+  | nofix_error
+  = addErrRn (precParseErr (ppr_op op1,fix1) (ppr_op op2,fix2))	`thenRn_`
+    returnRn (ConOpPatIn p1 op2 fix2 p2)
 
-rnStmt (BindStmt pat expr src_loc)
-  = pushSrcLocRn src_loc $
-    rnExpr expr		 		`thenRn` \ (expr', fvExpr) ->
-    let
-	binders = collectPatBinders pat
-    in
-    newLocalNames "variable in do binding"
-	 (binders `zip` repeat src_loc)	`thenRn` \ new_binders ->
-    extendSS new_binders (rnPat pat) 	`thenRn` \ pat' ->
+  | associate_right
+  = mkConOpPatRn p12 op2 fix2 p2		`thenRn` \ new_p ->
+    returnRn (ConOpPatIn p11 op1 fix1 new_p)
 
-    returnRn ((BindStmt pat' expr' src_loc, new_binders), fvExpr)
+  where
+    (nofix_error, associate_right) = compareFixity fix1 fix2
 
-rnStmt (ExprStmt expr src_loc)
-  = 
-    rnExpr expr	 			`thenRn` \ (expr', fvs) ->
-    returnRn ((ExprStmt expr' src_loc, []), fvs)
+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 -> Name -> RenamedMatch -> RnMS ()
 
-rnStmt (LetStmt binds)
-  = rnBinds binds	`thenRn` \ (binds', binds_fvs, new_binders) ->
-    returnRn ((LetStmt binds', new_binders), binds_fvs)
+checkPrecMatch False fn match
+  = returnRn ()
 
+checkPrecMatch True op (Match _ (p1:p2:_) _ _)
+	-- True indicates an infix lhs
+  = getModeRn 		`thenRn` \ mode ->
+	-- See comments with rnExpr (OpApp ...)
+    if isInterfaceMode mode
+	then returnRn ()
+	else checkPrec op p1 False	`thenRn_`
+	     checkPrec op p2 True
+
+checkPrecMatch True op _ = panic "checkPrecMatch"
+
+checkPrec op (ConOpPatIn _ op1 _ _) right
+  = lookupFixityRn op	`thenRn` \  op_fix@(Fixity op_prec  op_dir) ->
+    lookupFixityRn op1	`thenRn` \ 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  = (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 pat right
+  = returnRn ()
+
+-- Check precedence of (arg op) or (op arg) respectively
+-- If arg is itself an operator application, its precedence should
+-- be higher than that of op
+checkSectionPrec left_or_right section op arg
+  = case arg of
+	OpApp _ op fix _ -> go_for_it (ppr_op op)     fix
+	NegApp _	 -> go_for_it pp_prefix_minus negateFixity
+	other		 -> returnRn ()
+  where
+    HsVar op_name = op
+    go_for_it pp_arg_op arg_fix@(Fixity arg_prec _)
+	= lookupFixityRn op_name	`thenRn` \ op_fix@(Fixity op_prec _) ->
+	  checkRn (op_prec < arg_prec)
+		  (sectionPrecErr (ppr_op op_name, op_fix) (pp_arg_op, arg_fix) section)
+\end{code}
+
+Consider
+\begin{verbatim}
+	a `op1` b `op2` c
+\end{verbatim}
+@(compareFixity op1 op2)@ tells which way to arrange appication, or
+whether there's an error.
+
+\begin{code}
+compareFixity :: Fixity -> Fixity
+	      -> (Bool,		-- Error please
+		  Bool)		-- Associate to the right: a op1 (b op2 c)
+compareFixity (Fixity prec1 dir1) (Fixity prec2 dir2)
+  = case prec1 `compare` prec2 of
+	GT -> left
+	LT -> right
+	EQ -> case (dir1, dir2) of
+			(InfixR, InfixR) -> right
+			(InfixL, InfixL) -> left
+			_		 -> error_please
+  where
+    right	 = (False, True)
+    left         = (False, False)
+    error_please = (True,  False)
 \end{code}
 
 %************************************************************************
 %*									*
-\subsubsection{Precedence Parsing}
+\subsubsection{Literals}
 %*									*
 %************************************************************************
 
-\begin{code}
-precParseExpr :: RenamedHsExpr -> RnM_Fixes s RenamedHsExpr
-precParsePat  :: RenamedPat -> RnM_Fixes s RenamedPat
-
-precParseExpr exp@(OpApp (NegApp e1) (HsVar op) e2)
-  = lookupFixity op		`thenRn` \ (op_fix, op_prec) ->
-    if 6 < op_prec then		
-	-- negate precedence 6 wired in
-	-- (-x)*y  ==> -(x*y)
-	precParseExpr (OpApp e1 (HsVar op) e2) `thenRn` \ op_app ->
-	returnRn (NegApp op_app)
-    else
-	returnRn exp
-
-precParseExpr exp@(OpApp (OpApp e11 (HsVar op1) e12) (HsVar op) e2)
-  = lookupFixity op		 `thenRn` \ (op_fix, op_prec) ->
-    lookupFixity op1		 `thenRn` \ (op1_fix, op1_prec) ->
-    case cmp op1_prec op_prec of
-      LT_  -> rearrange
-      EQ_  -> case (op1_fix, op_fix) of
-		(INFIXR, INFIXR) -> rearrange
-		(INFIXL, INFIXL) -> returnRn exp
-		_ -> getSrcLocRn `thenRn` \ src_loc ->
-		     failButContinueRn exp
-		     (precParseErr (op1,op1_fix,op1_prec) (op,op_fix,op_prec) src_loc)
-      GT__ -> returnRn exp
-  where
-    rearrange = precParseExpr (OpApp e12 (HsVar op) e2) `thenRn` \ e2' ->
-	        returnRn (OpApp e11 (HsVar op1) e2')
+When literals occur we have to make sure
+that the types and classes they involve
+are made available.
 
-precParseExpr exp = returnRn exp
+\begin{code}
+litFVs (HsChar c)
+   = checkRn (inCharRange c) (bogusCharError c) `thenRn_`
+     returnRn (unitFV charTyCon_name)
+
+litFVs (HsCharPrim c)         = returnRn (unitFV (getName charPrimTyCon))
+litFVs (HsString s)           = returnRn (mkFVs [listTyCon_name, charTyCon_name])
+litFVs (HsStringPrim s)       = returnRn (unitFV (getName addrPrimTyCon))
+litFVs (HsInt i)	      = returnRn (unitFV (getName intTyCon))
+litFVs (HsIntPrim i)          = returnRn (unitFV (getName intPrimTyCon))
+litFVs (HsFloatPrim f)        = returnRn (unitFV (getName floatPrimTyCon))
+litFVs (HsDoublePrim d)       = returnRn (unitFV (getName doublePrimTyCon))
+litFVs (HsLitLit l bogus_ty)  = lookupOrigName cCallableClass_RDR	`thenRn` \ cc ->   
+				returnRn (unitFV cc)
+litFVs lit		      = pprPanic "RnExpr.litFVs" (ppr lit)	-- HsInteger and HsRat only appear 
+									-- in post-typechecker translations
+
+rnOverLit (HsIntegral i)
+  | inIntRange i
+  = returnRn (HsIntegral i, unitFV fromIntegerName)
+  | otherwise
+  = lookupOrigNames [fromInteger_RDR, plusInteger_RDR, timesInteger_RDR]	`thenRn` \ ns ->
+	-- Big integers are built, using + and *, out of small integers
+	-- [No particular reason why we use fromIntegerName in one case can 
+	--  fromInteger_RDR in the other; but plusInteger_RDR means we 
+	--  can get away without plusIntegerName altogether.]
+    returnRn (HsIntegral i, ns)
+
+rnOverLit (HsFractional i)
+  = lookupOrigNames [fromRational_RDR, ratioDataCon_RDR, 
+		     plusInteger_RDR, timesInteger_RDR]  `thenRn` \ ns ->
+	-- We have to make sure that the Ratio type is imported with
+	-- its constructor, because literals of type Ratio t are
+	-- built with that constructor.
+	-- The Rational type is needed too, but that will come in
+	-- when fractionalClass does.
+	-- The plus/times integer operations may be needed to construct the numerator
+	-- and denominator (see DsUtils.mkIntegerLit)
+    returnRn (HsFractional i, ns)
+\end{code}
 
+%************************************************************************
+%*									*
+\subsubsection{Assertion utils}
+%*									*
+%************************************************************************
 
-precParsePat pat@(ConOpPatIn (NegPatIn e1) op e2)
-  = lookupFixity op		`thenRn` \ (op_fix, op_prec) ->
-    if 6 < op_prec then	
-	-- negate precedence 6 wired in
-	getSrcLocRn `thenRn` \ src_loc ->
-	failButContinueRn pat (precParseNegPatErr (op,op_fix,op_prec) src_loc)
-    else
-	returnRn pat
-
-precParsePat pat@(ConOpPatIn (ConOpPatIn p11 op1 p12) op p2)
-  = lookupFixity op		 `thenRn` \ (op_fix, op_prec) ->
-    lookupFixity op1		 `thenRn` \ (op1_fix, op1_prec) ->
-    case cmp op1_prec op_prec of
-      LT_  -> rearrange
-      EQ_  -> case (op1_fix, op_fix) of
-		(INFIXR, INFIXR) -> rearrange
-		(INFIXL, INFIXL) -> returnRn pat
-		_ -> getSrcLocRn `thenRn` \ src_loc ->
-		     failButContinueRn pat
-		       (precParseErr (op1,op1_fix,op1_prec) (op,op_fix,op_prec) src_loc)
-      GT__ -> returnRn pat
-  where
-    rearrange = precParsePat (ConOpPatIn p12 op p2) `thenRn` \ p2' ->
-	        returnRn (ConOpPatIn p11 op1 p2')
+\begin{code}
+mkAssertExpr :: RnMS (RenamedHsExpr, FreeVars)
+mkAssertExpr =
+  lookupOrigName assertErr_RDR		`thenRn` \ name ->
+  getSrcLocRn    			`thenRn` \ sloc ->
 
-precParsePat pat = returnRn pat
+    -- if we're ignoring asserts, return (\ _ e -> e)
+    -- if not, return (assertError "src-loc")
 
+  if opt_IgnoreAsserts then
+    getUniqRn				`thenRn` \ uniq ->
+    let
+     vname = mkSysLocalName uniq SLIT("v")
+     expr  = HsLam ignorePredMatch
+     loc   = nameSrcLoc vname
+     ignorePredMatch = Match [] [WildPatIn, VarPatIn vname] Nothing 
+                             (GRHSs [GRHS [ExprStmt (HsVar vname) loc] loc]
+			            EmptyBinds Nothing)
+    in
+    returnRn (expr, unitFV name)
+  else
+    let
+     expr = 
+          HsApp (HsVar name)
+	        (HsLit (HsString (_PK_ (showSDoc (ppr sloc)))))
 
-data INFIX = INFIXL | INFIXR | INFIXN
+    in
+    returnRn (expr, unitFV name)
 
-lookupFixity :: RnName -> RnM_Fixes s (INFIX, Int)
-lookupFixity op
-  = getExtraRn `thenRn` \ fixity_fm ->
-    case lookupUFM fixity_fm op of
-      Nothing           -> returnRn (INFIXL, 9)
-      Just (InfixL _ n) -> returnRn (INFIXL, n)
-      Just (InfixR _ n) -> returnRn (INFIXR, n)
-      Just (InfixN _ n) -> returnRn (INFIXN, n)
 \end{code}
 
+%************************************************************************
+%*									*
+\subsubsection{Errors}
+%*									*
+%************************************************************************
+
 \begin{code}
-negPatErr pat src_loc
-  = addErrLoc src_loc "prefix `-' not applied to literal in pattern" ( \sty ->
-    ppr sty pat) 
-
-precParseNegPatErr op src_loc
-  = addErrLoc src_loc "precedence parsing error" (\ sty ->
-    ppBesides [ppStr "prefix `-' has lower precedence than ", pp_op sty op, ppStr " in pattern"])
-
-precParseErr op1 op2 src_loc
-  = addErrLoc src_loc "precedence parsing error" (\ sty -> 
-    ppBesides [ppStr "cannot mix ", pp_op sty op1, ppStr " and ", pp_op sty op2,
-	       ppStr " in the same infix expression"])
-
-pp_op sty (op, fix, prec) = ppBesides [pprOp sty op, ppLparen, pp_fix fix, ppSP, ppInt prec, ppRparen]
-pp_fix INFIXL = ppStr "infixl"
-pp_fix INFIXR = ppStr "infixr"
-pp_fix INFIXN = ppStr "infix"
+ppr_op op = quotes (ppr op)	-- Here, op can be a Name or a (Var n), where n is a Name
+ppr_opfix (pp_op, fixity) = pp_op <+> brackets (ppr fixity)
+pp_prefix_minus = ptext SLIT("prefix `-'")
+
+dupFieldErr str (dup:rest)
+  = hsep [ptext SLIT("duplicate field name"), 
+          quotes (ppr dup),
+	  ptext SLIT("in record"), text str]
+
+precParseErr op1 op2 
+  = hang (ptext SLIT("precedence parsing error"))
+      4 (hsep [ptext SLIT("cannot mix"), ppr_opfix op1, ptext SLIT("and"), 
+	       ppr_opfix op2,
+	       ptext SLIT("in the same infix expression")])
+
+sectionPrecErr op arg_op section
+ = vcat [ptext SLIT("The operator") <+> ppr_opfix op <+> ptext SLIT("of a section"),
+	 nest 4 (ptext SLIT("must have lower precedence than the operand") <+> ppr_opfix arg_op),
+	 nest 4 (ptext SLIT("In the section:") <+> quotes (ppr section))]
+
+nonStdGuardErr guard
+  = hang (ptext
+    SLIT("accepting non-standard pattern guards (-fglasgow-exts to suppress this message)")
+    ) 4 (ppr guard)
+
+patSigErr ty
+  =  (ptext SLIT("Illegal signature in pattern:") <+> ppr ty)
+	$$ nest 4 (ptext SLIT("Use -fglasgow-exts to permit it"))
+
+patSynErr e 
+  = sep [ptext SLIT("Pattern syntax in expression context:"),
+	 nest 4 (ppr e)]
+
+doStmtListErr e
+  = sep [ptext SLIT("`do' statements must end in expression:"),
+	 nest 4 (ppr e)]
+
+bogusCharError c
+  = ptext SLIT("character literal out of range: '\\") <> int c <> char '\''
 \end{code}