[Hackage] #483: separate preferred versions into hacks and real preferred versions

[Hackage]

#483: separate preferred versions into hacks and real preferred versions
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  Reporter:  duncan             |        Owner:         
      Type:  enhancement        |       Status:  new    
  Priority:  normal             |    Milestone:         
 Component:  hackageDB website  |      Version:  1.6.0.1
  Severity:  normal             |     Keywords:         
Difficulty:  unknown            |   Ghcversion:         
  Platform:                     |  
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 We have the "preferred-versions" file in the hackage index. This is used
 by cabal-install. It has a dual purpose which we should try to separate.

 The first is for things like "base < 4", to make up for the fact that so
 many older packages do not specify a version of base. This is basically a
 hack. It's not that we really would prefer people to use base 3.

 On the other hand it is useful to be able to put experimental versions of
 packages on hackage and not have them be the default version. For example
 HaXml still declares that 1.13.x is the stable version with 1.19.x the
 current development version. In the latter case the default (unversioned)
 package package should point to the preferred version (ie 1.13.x).

 So it would be useful to separate the hacks from the real preferred
 versions. The cabal-install tool might treat the two slightly differently
 and the hackage db website should only consider the latter.

-- 
Ticket URL: <http://hackage.haskell.org/trac/hackage/ticket/483>
Hackage <http://haskell.org/cabal/>
Hackage: Cabal and related projects