[GHC] #1744: treat byte order mark as zero-width whitespace

[GHC]

#1744: treat byte order mark as zero-width whitespace
--------------------------------+-------------------------------------------
  Reporter:  igloo              |          Owner:         
      Type:  feature request    |         Status:  new    
  Priority:  normal             |      Milestone:         
 Component:  Compiler (Parser)  |        Version:  6.8    
  Severity:  normal             |       Keywords:         
Difficulty:  Unknown            |             Os:  Unknown
  Testcase:                     |   Architecture:  Unknown
--------------------------------+-------------------------------------------
 The U+FEFF ZERO WIDTH NO-BREAK SPACE Unicode character, better known as
 BYTE ORDER MARK (BOM), currently gives a lexical error:

 {{{
 $ printf '\xEF\xBB\xBF\nz = "str"\n' > z.hs
 $ ghci z.hs
 GHCi, version 6.8.0.20070927: http://www.haskell.org/ghc/  :? for help
 Loading package base ... linking ... done.

 z.hs:1:0: lexical error at character '\65279'
 Failed, modules loaded: none.
 Prelude> Leaving GHCi.
 }}}

 The character is only in categories Other and Format, not Space, but I
 think we should lex it as whitespace anyway (with zero width for the
 purposes of the layout rule). Ideally Haskell' would do likewise.

-- 
Ticket URL: <http://hackage.haskell.org/trac/ghc/ticket/1744>
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