[GHC] #14648: ghc-pkg does handle unitids

[GHC]

#14648: ghc-pkg does handle unitids
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        Reporter:  lspitzner         |                Owner:  (none)
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:
       Component:  ghc-pkg           |              Version:  8.2.1
      Resolution:                    |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  None/Unknown      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by lspitzner):

 Can't we just check if `show`/`disp` on the parsed value yields the input
 string, and print a warning if there is a difference? Is there any risk
 for false positives (cases where `input /= disp (read input)` for package-
 version strings without a tag)? Capitalization comes to mind, but i don't
 think it is a problem here, right?

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/14648#comment:4>
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