[GHC] #1215: GHC fails to respect the maximal munch rule while lexing "qualified reservedids"

[GHC]

#1215: GHC fails to respect the maximal munch rule while lexing "qualified
reservedids"
-------------------------------------------------+--------------------------
    Reporter:  Stefan O'Rear <stefanor at cox.net>  |       Owner:         
        Type:  bug                               |      Status:  new    
    Priority:  low                               |   Milestone:         
   Component:  Compiler (Parser)                 |     Version:  6.6    
    Severity:  normal                            |    Keywords:         
  Difficulty:  Unknown                           |    Testcase:         
Architecture:  Unknown                           |          Os:  Unknown
-------------------------------------------------+--------------------------
The following program I believe is legal haskell 98:

 {{{
 module Main where

 t = 2
 defaul _ = return ()
 main = Main.default
 }}}

 since Main.default is an illegal lexeme, but Main.defaul is a perfectly
 good qvarid.  however ghci rejects it:

 {{{
 Bar.hs:5:12: parse error on input `default'
 }}}

 Something very similar to this is documented, but only in the qvarsym
 case. This appears fairly easy to fix using extra rules in the lexer; a
 flex lexer that does what I consider correct can be found at
 http://members.cox.net/stefanor/h98lexer.l.

-- 
Ticket URL: <http://hackage.haskell.org/trac/ghc/ticket/1215>
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