[commit: Cabal] master: First version of the top-down package dependency resolver (bc07102)

[Paolo Capriotti]

Repository : ssh://darcs.haskell.org//srv/darcs/packages/Cabal

On branch  : master

http://hackage.haskell.org/trac/ghc/changeset/bc07102a7beb45b7ea6744c347c3f34f209b1331

>---------------------------------------------------------------

commit bc07102a7beb45b7ea6744c347c3f34f209b1331
Author: Duncan Coutts <duncan at haskell.org>
Date:   Wed May 28 21:58:04 2008 +0000

    First version of the top-down package dependency resolver
    This is a new dependency resolver that produces valid install plans.
    It works in polynomial time however because the search space is
    exponential in size it is not guaranteed to find a solution even if
    one exists. It works by generating and then exploring the search
    space represented as a lazy tree. It uses constraints to prune
    choices and heuristics when guesses are necessary. Currently it can
    generate install plans for 99% of the packages on hackage. The
    remaining 6 packages should be doable with two extra tricks.
    It is not finished and is not yet usable in practice.

 cabal-install/Hackage/Dependency.hs                |    2 +
 cabal-install/Hackage/Dependency/TopDown.hs        |  400 ++++++++++++++++++++
 .../Hackage/Dependency/TopDown/Constraints.hs      |  244 ++++++++++++
 cabal-install/Hackage/Dependency/TopDown/Types.hs  |   77 ++++
 cabal-install/Hackage/Dependency/Types.hs          |   27 ++
 cabal-install/cabal-install.cabal                  |    5 +-
 6 files changed, 754 insertions(+), 1 deletions(-)


Diff suppressed because of size. To see it, use:

    git show bc07102a7beb45b7ea6744c347c3f34f209b1331