[GHC] #8637: Infix declaration on operators ending on backslash

[GHC]

#8637: Infix declaration on operators ending on backslash
----------------------------+----------------------------------------------
       Reporter:            |             Owner:
  jcristovao                |            Status:  new
           Type:  bug       |         Milestone:
       Priority:  normal    |           Version:  7.7
      Component:  Compiler  |  Operating System:  Linux
       Keywords:            |   Type of failure:  GHC rejects valid program
   Architecture:  x86_64    |         Test Case:
  (amd64)                   |          Blocking:
     Difficulty:  Unknown   |
     Blocked By:            |
Related Tickets:            |
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 Hi,

 I was trying the latest GHC Head (version 7.7.20131227), when I noticed a
 regression. I don't know if this is intended behaviour or not. This
 compiled ok under 7.6.3

 {{{
 (?&&\) :: (Monoid a) => a -> (a -> Bool) -> a
 (?&&\) value f = if f value then value else mempty
 infixl 1 ?&&\
 }}}

 Under 7.7, the infixl declaration only works if I double escape it.

 {{{
 infixl 1 ?&&\\
 }}}

 Is this intended?

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Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/8637>
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