[ocaml-platform] Sources of the aspcud external solver

[Roberto Di Cosmo]

I just met in the Irill corridors another person interested in
using aspcud as an external solver for opam, and that had
difficulties finding the pointer to upstream sources.

It seems then useful to paste here information that ended
up scattered on github, private mail exchanges, and the like,
in case somebody else want to get an external solver running
on her/his system

1) the page https://github.com/ocaml/opam/wiki/Distributions maintained by
   Anil contains current information on the porting status of the external
   solvers on different architectures/OS

2) the official page with information on aspcud is actually
   out there:

     http://www.cs.uni-potsdam.de/wv/aspcud/

   Since this tool is built on top of an ASP solver distributed
   by the Potassco team and available here

     http://potassco.sourceforge.net/

   you need to first make clasp and gringo run on your system,
   and yes, there is information on what you need to do to make
   this work

   http://sourceforge.net/p/potassco/wiki/Home/

 3) the developer of aspcud, Roland Kaminski, is active, and willing to help;
    he has already incorporated upstream several changes that should make
    porting/packaging easier (in particular, the shell script wrapper used
    in 1.8 is gone). Here is the changelog and the url to the upstream version

        added support for old-style criteria
        added an install target (supports DESTDIR)
        replaced bash/python script with a small C program
        should build on MacOS X without problems now

    http://svn.code.sf.net/p/potassco/code/trunk/aspcud/

Cheers

--
Roberto