[Distutils] "just use debian"

[David Cournapeau]

Josselin Mouette wrote:
>
> As I understand PEP 345, it proposes to introduce dependencies based on
> module names, not on project names. This is one of the key points where
> it is superior to setuptools; especially, if developers correctly change
> the module name when changing the API, the dependencies are clear and
> reliable.

I don't understand this. Why do you need to change the module name ? You
need to be able to request a given version of the module, yes, but you
don't need to change the name itself. Changing name is an implementation
detail of the concept of retrieving a particular version, no ?

I mean, when I build my C program against the glibc, I never have to
change my compiler commands depending on which version of glibc I want.
Internally, this is handled by versioned sonames, at the link and load
stage, yes, but only because it is "easy" to do and doable for C,
because the library itself is never referenced in the code; IOW, there
is the link process in C and similar compiled languages which use the
name changes. But other languages use something different; I don't claim
any deep understanding of the scheme, but mono uses a totally different
scheme to handle versioning:

http://www.mono-project.com/Assemblies_and_the_GAC

Does mono cause problems to debian ? I think this kind of system is much
more adapted to python than the C model is, because C has this two steps
thing that python does not have.

Of couse, it is more complicated than changing names. But I fear that
people wants their cake and eating it: you can't have well maintained
packages and reliability without thinking about API/ABI issues. There
has to be a balance between OS distributors need (mostly only one
version) and other people needs who may need several parallel
installations.

I think setuptools and the whole eggs thing makes it well too easy to
install several versions at the same time, making some people naively
thinking it solves the dependency issues, without thinking that it
replaces a kind of dll hell by a dependency hell. But OTOH, as a
developer, I need to be able to develop my packages, distribute them,
and breaking them from time to time before I reach 1.0. That's almost
requirement of open source development, at least if you follow the
release early/release often.

cheers,

David