Hi all,
I'm posting my proposal as Gregor ask me to. Its purpose is to
regorganise python in order to make multiple versions and modules
at the same time.
1) Problem:
- we want python 2 to enter debian ASAP
- we do not want to duplicate packages for python 2
- the python version number is hard coded in the path to
python modules.
2) Proposal:
I'm proposing to reorganise the python tree as follows (I'm considering
only site packages in this case, are this is what is problematic) :
/usr/lib/python/1.5/site-packages
This directory contains python 1.5.2 modules that are not compatible
with greater version of python (i.e. 2.0)
/usr/lib/python/2.0/site-packages
This directory contains python 2.0-specific modules. These are not
compatible
with earlier versions of python (i.e. 1.5).
/usr/lib/python/site-packages
This directory contains python packages that are runnable "with
all pythons".
3) Sceneries:
. Python 1.5 was installed and we decide to install 2.0
python 1.5 specific packages are installed in ...python/1.5/site-packages
other packages are installed in ...python/site-packages
* we make /usr/bin/python point to python 2 thanks to alternatives
* we run a compileall.py in python/site-packages in order to
get them byte-recompiled for 2.0
. 1.5 and 2.0 are both present on the system
and we uninstall 1.5
* nothing to do
. 1.5 and 2.0 are both present on the system
and we want to uninstall 2.0
* we remove the alternative so that /usr/bin/python points to 1.5
* we run compileall.py in python/site-packages in order to get them
byte-recompiled for the earlier version (i.e. 1.5)
. 2.0 in the only one installed
* nothing to do
4) Modifiying the interpreters:
.The interpreters have to dynamically look for the following path, in
the following order:
- /usr/lib/python/<their version>/site-packages
- /usr/lib/python/site-packages
. postint
Add compileall for /usr/lib/python/site-packages
. postrm
Add compileall for /usr/lib/python/site-packages if another
interpreter is present on the system.
. control
Add a versioned provides, Provides: python (= 2.0)
5) Modifying site packages:
People will have to check the compatibility of they modules with
1.5 and 2.0 and install them in the new tree as explained in the
proposal.
So, 3 kinds of dependencies :
Depends: python (>= 2.0) for /usr/lib/python/2.0/site-packages
Depdens: python (>= 1.5), python (<= 1.5.2) for
/usr/lib/python/1.5/site-packages
Depends: python (>= 1.5) for /usr/lib/python/site-packages
Did I miss something ?
6) If this can be implemented, we'll have to:
- make new python 1.5 packages
- release python 2.0 in experimental
- change our packages to test the new implementation
- fill bug report for all python packages
- once tested, we'll be ready for woody.
Any comment, ideas ?
Thanks.
Cheers,
--
Jérôme Marant <[EMAIL PROTECTED]>
http://jerome.marant.free.fr
