[Chicken-hackers] scan, list and override

[Felix]

Hello!


Perhaps you know the situation: you have a working application with a
bunch of dependencies and want to move it to a new machine, or do a
reinstall, or want to demonstrate it to someone else. In the meantime,
some egg maintainer has release the shiny new version 2.0 of some
egg-dependency, that isn't really important to your app, yet
introduces some incompatibility (you know the rest). To help with
such troubles, I have added a few options to chicken-install and
chicken-status to allow "overriding" egg versions, in a brute-force
manner.

"chicken-install -scan DIR" will scan a directory following the repository
layout of the SVN repository and list the most recent available versions
in the directory.

"chicken-status -list" will list eggs+versions for install extensions
in the same format as "-scan".

"chicken-install -override FILENAME ..." will override any explicit
or implicit versions for extensions or extensions-dependencies as
given in FILENAME, which is usually generated by "-scan" or "-list".

Overrides may also be specified in your "setup.defaults" file.

This is a bit crude, but allows nailing down the versions of eggs
you want to have installed, independent of what happened in the
egg repopsitory recently.

(see "experimental" branch)


cheers,
felix