[GHC] #836: rebindable if-then-else syntax

[GHC]

#836: rebindable if-then-else syntax
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    Reporter:  nibro              |        Owner:  SamAnklesaria
        Type:  feature request    |       Status:  new          
    Priority:  normal             |    Milestone:  _|_          
   Component:  Compiler (Parser)  |      Version:  6.13         
    Keywords:                     |     Testcase:  N/A          
   Blockedby:                     |   Difficulty:  Unknown      
          Os:  Unknown/Multiple   |     Blocking:               
Architecture:  Unknown/Multiple   |      Failure:  None/Unknown 
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Comment(by SamAnklesaria):

 As there are many libraries that use `if` syntax where a polymorphic
 function would not suffice, I've decided to make rebindable syntax only
 accessible through a language extension flag (currently named
 RebindableIfStatements). While the function `ifThenElse` is a part of the
 Prelude regardless, it is not substituted for `if` statements unless
 RebindableIfStatements is on.

 Is this okay?

-- 
Ticket URL: <http://hackage.haskell.org/trac/ghc/ticket/836#comment:26>
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