[Python-Dev] What to do about PEP 229?

[A.M. Kuchling]

I began writing the fabled fancy setup script described in PEP 229,
and then realized there was duplication going on here.  The code in
setup.py would need to know what libraries, #defines, &c., are needed
by each module in order to check if they're needed and set them.  But
if Modules/Setup can be used to override setup.py's behaviour, then
much of this information would need to be in that file, too; the
details of compiling a module are in two places. 

Possibilities:

1) Setup contains fully-loaded module descriptions, and the setup
   script drops unneeded bits.  For example, the socket module
   requires -lnsl on some platforms.  The Setup file would contain
   "socket socketmodule.c -lnsl" on all platforms, and setup.py would 
   check for an nsl library and only use if it's there.  

   This seems dodgy to me; what if -ldbm is needed on one platform and
   -lndbm on another?

2) Drop setup completely and just maintain setup.py, with some
   different overriding mechanism.  This is more radical.  Adding a
   new module is then not just a matter of editing a simple text file;
   you'd have to modify setup.py, making it more like maintaining an
   autoconf script.
  
Remember, the underlying goal of PEP 229 is to have the out-of-the-box
Python installation you get from "./configure;make" contain many more
useful modules; right now you wouldn't get zlib, syslog, resource, any
of the DBM modules, PyExpat, &c.  I'm not wedded to using Distutils to
get that, but think that's the only practical way; witness the hackery
required to get the DB module automatically compiled.  

You can also wave your hands in the direction of packagers such as
ActiveState or Red Hat, and say "let them make to compile everything".
But this problem actually inconveniences *me*, since I always build
Python myself and have to extensively edit Setup, so I'd like to fix
the problem.

Thoughts? 

--amk