[GHC] #9824: Pattern quotations warn about unused matches

21 Nov 2014

      #9824: Pattern quotations warn about unused matches
-------------------------------------+-------------------------------------
       Reporter:  goldfire           |                   Owner:
           Type:  bug                |                  Status:  new
       Priority:  normal             |               Milestone:
      Component:  Template Haskell   |                 Version:  7.8.3
       Keywords:                     |        Operating System:
   Architecture:  Unknown/Multiple   |  Unknown/Multiple
     Difficulty:  Unknown            |         Type of failure:
     Blocked By:                     |  None/Unknown
Related Tickets:                     |               Test Case:
                                     |                Blocking:
                                     |  Differential Revisions:
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 If I say

 {{{
 {-# LANGUAGE TemplateHaskell #-}
 {-# OPTIONS_GHC -fwarn-unused-matches #-}

 module Pat where

 foo = [p| (x, y) |]
 }}}

 I get

 {{{
 Pat.hs:6:12: Warning: Defined but not used: ‘x’

 Pat.hs:6:15: Warning: Defined but not used: ‘y’
 }}}

 This is silly.

 Patch forthcoming.

--
Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/9824
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