[GHC] #7162: RULES that never fire (automatically)

[GHC]

#7162: RULES that never fire (automatically)
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  Reporter:  andygill          |          Owner:                  
      Type:  feature request   |         Status:  new             
  Priority:  normal            |      Milestone:  7.8.1           
 Component:  Compiler          |        Version:  7.7             
Resolution:                    |       Keywords:                  
        Os:  Unknown/Multiple  |   Architecture:  Unknown/Multiple
   Failure:  None/Unknown      |     Difficulty:  Unknown         
  Testcase:                    |      Blockedby:                  
  Blocking:                    |        Related:                  
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Comment(by afarmer):

 So while documenting this, I realized this patch makes an unintended
 change. Namely, the INLINE pragma uses the same parser rules for
 activation as the RULES pragma. So it is now possible to write:

 {-# INLINE [~] ... #-}
 and
 {-# NOINLINE [~] ... #-}

 Looking at RdrHsSyn.lhs, the first case (INLINE [~]) is equivalent to
 NOINLINE. Worryingly, I have yet to figure out how the second case
 (NOINLINE [~]) behaves.

 So as I see it, there are two possible solutions.

 1. I submit a new patch to the parser that separates the activation
 parsing for RULES and INLINE so RULES [~] is possible but INLINE [~] is
 not.

 2. I figure out what NOINLINE [~] means and document that.

 Opinions? I'm inclined towards option 1, as I think it'll be less
 confusing for the user.

-- 
Ticket URL: <http://hackage.haskell.org/trac/ghc/ticket/7162#comment:10>
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