[PyKDE] Multiple PyQt version in one Python installation

[Phil Thompson]

On Saturday 04 November 2006 7:47 pm, Simon Edwards wrote:
> Hello,
>
> One of the things that I would like to see in PyKDE 4 is the possibility to
> install different versions PyQt into the same Python installation in the
> event that backward compatibility in libsip needs to be broken.
>
> Anyway, I've done a bit of exploratory programming regarding making it
> possible to install and use two versions of SIP+PyQt which use a different
> libsips. The idea is that different versions of PyQt could be installed as
> different modules (PyQt_v4, and PyQt_v5 for example), and using a couple of
> module loading tricks it should be possible for PyQt4 programs to work so
> as they now work. Python programs that contain a C++ class compiled against
> a specific version of libsip, can then specify which version of libsip they
> need.
>
> To illustrate by example:
> 	...
> 	from PyQt import QtCore
> 	...
>
> Gets the default latest PyQt version, while this explicitly requests a the
> installed version of PyQt that uses sip2.
>
> 	...
> 	import sip2
> 	from PyQt import QtCore
> 	...
>
> Later the program could load its own C++ class that uses the same version
> of libsip without the whole thing blowing up.
>
> My experiment is in the zip file attached to this email. (I hope it gets
> through to the list).
>
> This would be very useful for PyKDE and KDE 4. Phil, what do you think?

Yuck. So, in the hypothetical case where a binary incompatibility is 
introduced you then go through all your existing applications and change the 
Python source code???

If you want module version dependencies then don't eggs give you what you 
need?

Why do you think there is something called libsip that a C++ class is compiled 
against?

Phil