[GHC] #2496: Invalid Eq/Ord instances in Data.Version

[GHC]

#2496: Invalid Eq/Ord instances in Data.Version
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        Reporter:  guest             |                   Owner:
            Type:  bug               |                  Status:  new
        Priority:  normal            |               Milestone:  7.12.1
       Component:  Core Libraries    |                 Version:  6.8.3
      Resolution:                    |                Keywords:
Operating System:  Unknown/Multiple  |            Architecture:
 Type of failure:  None/Unknown      |  Unknown/Multiple
      Blocked By:                    |               Test Case:
 Related Tickets:                    |                Blocking:
                                     |  Differential Revisions:  Phab:D395
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Comment (by rodlogic):

 Replying to [comment:19 zilinc]:
 > I feel it's too late to object, so I'll ask a question instead. I'm
 developing a software, in which I use the `VersionTags` field to store the
 git commit hash in order to know under which git revision my software is
 compiled. It's implemented by a hook in `Setup.hs`. So that the
 `showVersion` function can print something like `MySoftware
 2.3.0.0-ce78942aed`, which is really handy for development. With the new
 changes in GHC, is there anywhere that I can put this piece of info? Or
 are you going to create another field in `PackageDescription` to keep
 extra notes?

 I also share the same feeling and sorry for being late to comment here.
 This is quite a common pattern out there. Removing versionTags to avoid
 the Eq/Ord inconsistency seems like the easiest approach but not the best
 one, imho. Why not stick to semver.org:
 MAJOR.MINOR.PATCH(-PRERELEASE)?(+tag)*, where:
  * "Pre-release versions have a lower precedence than the associated
 normal version"
  * "Build metadata SHOULD be ignored when determining version precedence"

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/2496#comment:21>
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