[GHC] #5108: Allow unicode sub/superscript symbols in both identifiers and operators

[GHC]

#5108: Allow unicode sub/superscript symbols in both identifiers and operators
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  Reporter:  mikhail.vorozhtsov  |          Owner:                  
      Type:  feature request     |         Status:  new             
  Priority:  normal              |      Milestone:  7.6.1           
 Component:  Compiler (Parser)   |        Version:  7.1             
Resolution:                      |       Keywords:  lexer unicode   
        Os:  Unknown/Multiple    |   Architecture:  Unknown/Multiple
   Failure:  None/Unknown        |     Difficulty:  Unknown         
  Testcase:                      |      Blockedby:                  
  Blocking:                      |        Related:                  
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Changes (by simonpj):

  * status:  patch => new


Comment:

 Mikhail,

 The first issue here is whether we ''want'' sub/superscripts (or indeed
 primes) on operators, and that's a language design question.  We tend
 towards "no" but if there was a clear consensus from the Unicode-aware
 Haskell community, we'd accept it.  The implementation questions are
 probably resolvable.

 Could you start a thread on glasgow-haskell-users to ask them?

 (A possible outcome might be that operators should not allow primes!  ie
 the current behaviour is inconsistent, as you point out.  And it's wierd
 that you can use Unicode primes but not Ascii ones!)

 Simon

-- 
Ticket URL: <http://hackage.haskell.org/trac/ghc/ticket/5108#comment:7>
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