seqMaybe is more commonly known as mplus

4 files changed, 15 insertions, 12 deletions

diff --git a/compiler/main/HscTypes.lhs b/compiler/main/HscTypes.lhs
index 6b1d05397d..72229ecca6 100644
--- a/compiler/main/HscTypes.lhs
+++ b/compiler/main/HscTypes.lhs
@@ -106,7 +106,7 @@ import BasicTypes	( Version, initialVersion, IPName,
 import IfaceSyn
 import FiniteMap	( FiniteMap )
 import CoreSyn		( CoreRule )
-import Maybes		( orElse, expectJust, catMaybes, seqMaybe )
+import Maybes		( orElse, expectJust, catMaybes )
 import Outputable
 import BreakArray
 import SrcLoc		( SrcSpan, Located )
@@ -120,6 +120,7 @@ import System.Time	( ClockTime )
 import Data.IORef
 import Data.Array       ( Array, array )
 import Data.List
+import Control.Monad    ( mplus )
 \end{code}
 
 
@@ -277,7 +278,7 @@ lookupIfaceByModule dflags hpt pit mod
 	-- in the HPT.  If it's not from the home package it's wrong to look
 	-- in the HPT, because the HPT is indexed by *ModuleName* not Module
     fmap hm_iface (lookupUFM hpt (moduleName mod)) 
-    `seqMaybe` lookupModuleEnv pit mod
+    `mplus` lookupModuleEnv pit mod
 
   | otherwise = lookupModuleEnv pit mod		-- Look in PIT only 
 
diff --git a/compiler/rename/RnNames.lhs b/compiler/rename/RnNames.lhs
index 359c470af7..029df843f0 100644
--- a/compiler/rename/RnNames.lhs
+++ b/compiler/rename/RnNames.lhs
@@ -52,7 +52,7 @@ import Util
 import ListSetOps
 import Data.List        ( partition, concatMap, (\\), delete )
 import IO		( openFile, IOMode(..) )
-import Monad		( when )
+import Monad		( when, mplus )
 \end{code}
 
 
@@ -1026,7 +1026,7 @@ lookupImpDeprec :: DynFlags -> HomePackageTable -> PackageIfaceTable
 -- The name is definitely imported, so look in HPT, PIT
 lookupImpDeprec dflags hpt pit gre
   = case lookupIfaceByModule dflags hpt pit (nameModule name) of
-	Just iface -> mi_dep_fn iface name `seqMaybe` 	-- Bleat if the thing, *or
+	Just iface -> mi_dep_fn iface name `mplus` 	-- Bleat if the thing, *or
 		      case gre_par gre of	
 			ParentIs p -> mi_dep_fn iface p	-- its parent*, is deprec'd
 			NoParent   -> Nothing
diff --git a/compiler/rename/RnSource.lhs b/compiler/rename/RnSource.lhs
index 8e2094d5a9..1cb2223367 100644
--- a/compiler/rename/RnSource.lhs
+++ b/compiler/rename/RnSource.lhs
@@ -51,12 +51,12 @@ import OccName
 import Outputable
 import SrcLoc		( Located(..), unLoc, noLoc )
 import DynFlags	( DynFlag(..) )
-import Maybes		( seqMaybe )
 import Maybe            ( isNothing )
-import Monad		( liftM, when )
 import BasicTypes       ( Boxity(..) )
 
 import ListSetOps    (findDupsEq, mkLookupFun)
+
+import Control.Monad
 \end{code}
 
 @rnSourceDecl@ `renames' declarations.
@@ -535,8 +535,8 @@ validRuleLhs foralls lhs
   where
     checkl (L loc e) = check e
 
-    check (OpApp e1 op _ e2)		  = checkl op `seqMaybe` checkl_e e1 `seqMaybe` checkl_e e2
-    check (HsApp e1 e2) 		  = checkl e1 `seqMaybe` checkl_e e2
+    check (OpApp e1 op _ e2)		  = checkl op `mplus` checkl_e e1 `mplus` checkl_e e2
+    check (HsApp e1 e2) 		  = checkl e1 `mplus` checkl_e e2
     check (HsVar v) | v `notElem` foralls = Nothing
     check other				  = Just other 	-- Failure
 
@@ -549,14 +549,14 @@ validRuleLhs foralls lhs
     check_e (HsLit e) 	  = Nothing
     check_e (HsOverLit e) = Nothing
 
-    check_e (OpApp e1 op _ e2) 	 = checkl_e e1 `seqMaybe` checkl_e op `seqMaybe` checkl_e e2
-    check_e (HsApp e1 e2)      	 = checkl_e e1 `seqMaybe` checkl_e e2
+    check_e (OpApp e1 op _ e2) 	 = checkl_e e1 `mplus` checkl_e op `mplus` checkl_e e2
+    check_e (HsApp e1 e2)      	 = checkl_e e1 `mplus` checkl_e e2
     check_e (NegApp e _)       	 = checkl_e e
     check_e (ExplicitList _ es)	 = checkl_es es
     check_e (ExplicitTuple es _) = checkl_es es
     check_e other		 = Just other	-- Fails
 
-    checkl_es es = foldr (seqMaybe . checkl_e) Nothing es
+    checkl_es es = foldr (mplus . checkl_e) Nothing es
 -}
 
 badRuleLhsErr name lhs bad_e
diff --git a/compiler/typecheck/TcClassDcl.lhs b/compiler/typecheck/TcClassDcl.lhs
index 624e97ffdb..2e7603b87c 100644
--- a/compiler/typecheck/TcClassDcl.lhs
+++ b/compiler/typecheck/TcClassDcl.lhs
@@ -60,6 +60,8 @@ import List
 import BasicTypes
 import Bag
 import FastString
+
+import Control.Monad
 \end{code}
 
 
@@ -552,7 +554,7 @@ isInstDecl (SigOrigin (ClsSkol _)) = False
 -- The renamer just puts the selector ID as the binder in the method binding
 -- but we must use the method name; so we substitute it here.  Crude but simple.
 find_bind sel_name meth_name binds
-  = foldlBag seqMaybe Nothing (mapBag f binds)
+  = foldlBag mplus Nothing (mapBag f binds)
   where 
 	f (L loc1 bind@(FunBind { fun_id = L loc2 op_name })) | op_name == sel_name
 		 = Just (L loc1 (bind { fun_id = L loc2 meth_name }))