> Btw, this is also how it works in Debian. Well, you can have multiple
> sources etc. but I actually think that was a mistake on their part - it
> just means that you don't have a complete map. You know - "Gnome 2?
> Well, if you add this line to your sources file then..."...
> 

It is not a mistake.  In fact, it's how you get the Squeak packages, and
it's how US citizens get packages they aren't allowed to download to
from their own country.

Still, after you download from all the entries in the sources list, the
local have a complete map to work with.



> >No it can't.  The author of a package has absolutely no way of 
> >knowing whether a prereq of "PackageC >1.0" will actually work...that 
> >is, unless they have the ability to see into the future.  ;)  Thus, 
> >such a pre-req specification is not only inaccurate, but it's also 
> >very problematic.

People are too hard on these versioning clauses.

First, this kind of clause is usually correct: it is usually a *bug* for
PackageC to break existing packages.  From that point of view the
incompatibility is a bug in PackageC.  In the open source world, such
bugs are expected to get fixed.  You don't need a crystal ball to
annotate your package as if other people are going to keep their
promisses.

Second, complex version-number clauses are unusual in practice, and you
can just say "depends-on PackageC".  If you do need to specif a version,
it is usually a restriction to a major version number, and/or a
restriction to be at least the version where some specific feature came
into existence.  If it's more complicated than that, then in fact the
other package is going through some complicated changes between
versions.  In that case, what in the world are you supposed to do? 
Luckily it's not that common.

Oh, and third, version dependencies only get so good anyway unless you
want to go through a year-long phase of integration testing.  You really
do want to try and get the newest packages, anyway....  So let's be
realistic about what any scheme can accomplish.


Lex