[commit: ghc] type-holes-branch: Fix the parser to support named holes (as "_a"). (44e1348)

Repository : ssh://darcs.haskell.org//srv/darcs/ghc

On branch  : type-holes-branch

http://hackage.haskell.org/trac/ghc/changeset/44e134827d31987cf8b9e067d0de1288106f823e

>---------------------------------------------------------------

commit 44e134827d31987cf8b9e067d0de1288106f823e
Author: Thijs Alkemade <[email protected]>
Date:   Thu Feb 23 16:17:03 2012 +0100

    Fix the parser to support named holes (as "_a").
    My changes to the parser to support named holes were in the wrong file (Parser.y instead of Parser.y.pp), so they never got committed.

>---------------------------------------------------------------

 compiler/parser/Lexer.x     |    2 --
 compiler/parser/Parser.y.pp |    8 ++++++--
 2 files changed, 6 insertions(+), 4 deletions(-)

diff --git a/compiler/parser/Lexer.x b/compiler/parser/Lexer.x
index 219e5ac..2f22a3d 100644
--- a/compiler/parser/Lexer.x
+++ b/compiler/parser/Lexer.x
@@ -529,8 +529,6 @@ data Token
   | ITdoubleunderscore
   | ITbackquote
   | ITsimpleQuote               --  '
-  | IToparenunderscore
-  | ITcparenunderscore
 
   | ITvarid   FastString        -- identifiers
   | ITconid   FastString
diff --git a/compiler/parser/Parser.y.pp b/compiler/parser/Parser.y.pp
index 2ffce86..026adba 100644
--- a/compiler/parser/Parser.y.pp
+++ b/compiler/parser/Parser.y.pp
@@ -207,7 +207,6 @@ incorrect.
 
 %token
  '_'            { L _ ITunderscore }            -- Haskell keywords
- '__'           { L _ ITdoubleunderscore }
  'as'           { L _ ITas }
  'case'         { L _ ITcase }          
  'class'        { L _ ITclass } 
@@ -324,6 +323,7 @@ incorrect.
  PREFIXQCONSYM  { L _ (ITprefixqconsym  _) }
 
  IPDUPVARID     { L _ (ITdupipvarid   _) }              -- GHC extension
+ HOLEVARID      { L _ (IThole     _) }
 
  CHAR           { L _ (ITchar     _) }
  STRING         { L _ (ITstring   _) }
@@ -1428,6 +1428,7 @@ aexp1   :: { LHsExpr RdrName }
 
 aexp2   :: { LHsExpr RdrName }
         : ipvar                         { L1 (HsIPVar $! unLoc $1) }
+        | hole                          { sL (getLoc $1) (HsHole  $! unLoc $1) }
         | qcname                        { L1 (HsVar   $! unLoc $1) }
         | literal                       { L1 (HsLit   $! unLoc $1) }
 -- This will enable overloaded strings permanently.  Normally the renamer turns HsString
@@ -1449,7 +1450,6 @@ aexp2   :: { LHsExpr RdrName }
         | '[' list ']'                  { LL (unLoc $2) }
         | '[:' parr ':]'                { LL (unLoc $2) }
         | '_'                           { L1 EWildPat }
-        | '__'                          { L1 (HsHole $! unLoc $1) }
         
         -- Template Haskell Extension
         | TH_ID_SPLICE          { L1 $ HsSpliceE (mkHsSplice 
@@ -1743,6 +1743,9 @@ dbind   : ipvar '=' exp                 { LL (IPBind (unLoc $1) $3) }
 ipvar   :: { Located (IPName RdrName) }
         : IPDUPVARID            { L1 (IPName (mkUnqual varName (getIPDUPVARID $1))) }
 
+hole    :: { Located RdrName }
+        : HOLEVARID             { sL (getLoc $1) (mkUnqual varName $ getHOLEVARID $1) }
+
 -----------------------------------------------------------------------------
 -- Warnings and deprecations
 
@@ -2062,6 +2065,7 @@ getQCONSYM      (L _ (ITqconsym  x)) = x
 getPREFIXQVARSYM (L _ (ITprefixqvarsym  x)) = x
 getPREFIXQCONSYM (L _ (ITprefixqconsym  x)) = x
 getIPDUPVARID   (L _ (ITdupipvarid   x)) = x
+getHOLEVARID    (L _ (IThole     x)) = x
 getCHAR         (L _ (ITchar     x)) = x
 getSTRING       (L _ (ITstring   x)) = x
 getINTEGER      (L _ (ITinteger  x)) = x