[GHC] #4176: reject unary minus in infix left hand side function bindings that resolve differently as expressions

[GHC]

#4176: reject unary minus in infix left hand side function bindings that resolve
differently as expressions
---------------------------+------------------------------------------------
  Reporter:  maeder        |          Owner:                   
      Type:  bug           |         Status:  new              
  Priority:  normal        |      Milestone:  7.2.1            
 Component:  Compiler      |        Version:  7.2.1            
Resolution:                |       Keywords:  fixity resolution
  Testcase:                |      Blockedby:                   
Difficulty:                |             Os:  Unknown/Multiple 
  Blocking:                |   Architecture:  Unknown/Multiple 
   Failure:  None/Unknown  |  
---------------------------+------------------------------------------------

Comment(by maeder):

 When converting a "pat" or a "funlhs" into a sequence for the fixity
 resolution, prefix minus signs are currently wrongly ignored as more
 atomic "lpat"s. If fixity resolution succeeds with these minus signs
 considered, then it should be checked if the argument of all minus signs
 is (still) a plain integer or float (as required by the grammar for
 "lpat").

 The current parsing of patterns (with minus signs deeper in the trees) is
 rather unhelpful, though.

-- 
Ticket URL: <http://hackage.haskell.org/trac/ghc/ticket/4176#comment:11>
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