[Hackage] #500: develop a tool to find the maximal consistent set of hackage packages

Hackage trac at galois.com
Sat Feb 14 13:34:46 EST 2009

#500: develop a tool to find the maximal consistent set of hackage packages
  Reporter:  duncan           |        Owner:     
      Type:  enhancement      |       Status:  new
  Priority:  normal           |    Milestone:     
 Component:  miscellaneous    |      Version:     
  Severity:  normal           |     Keywords:     
Difficulty:  project(> week)  |   Ghcversion:     
  Platform:                   |  
 To a great extent the point of libraries is code re-use. It follows that
 is it useful to be able to install and use two packages simultaneously.
 The extension of this is that we would like to know the maximal set of
 packages that we can install consistently. Them being consistent implies
 that we can use any of them in another package and have consistent

 If we knew a package was within the maximal subset then we can give it a
 positive mark on hackage. We may also be able to encourage package authors
 to update their dependencies to as to get their packages within this set.

 Calculating the maximal consistent subset is certainly an NP-complete
 problem. It is at least as hard as working out if any single package is
 installable and that is already NP-complete. However we do not necessarily
 have to get an exact maximal set, approximation would probably do. We
 would also like to influence the choice of the set by the importance of
 packages, especially when it comes to resolving choices about divisive
 packages (see #499).

 We would also like to influence the choices by manually supplied

 This can probably be implemented as an extension of the standard package
 dependency resolution algorithm and using the code developed for ticket

Ticket URL: <http://hackage.haskell.org/trac/hackage/ticket/500>
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