Re: [Distutils] desirability of multiple, divergent Python instances

Ben Finney wrote:

Greg Ewing writes:

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Gael Varoquaux wrote:

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a second Python needs to be installed on top of the system Python to add modules to it. Maybe the system should come with two pythons installed, one for use by the system and the other for users to add things to. Or at least be set up so that it appears that way -- they might share files under the hood.

I can't see how this is a good idea. I've seen it mentioned multiple times in this thread, but without justification.

It's my position that the Python instance one uses for development should diverge as little as possible from the default system instance. Otherwise one is actively pursuing a recipe for dependency failures when one eventually deploys the result.

Yes, there should be a way to deploy the code one is actively developing and testing to some location that will not affect the rest of the operation of the system. That is a far cry from asking that there should be multiple, divergent Python instances on the system.

The further step of saying that the operating system should not use the same Python instance as a "user" on the system (and note that the line between those is far from clear), but instead should use some Python instance that behaves differently from every other use of Python on the system, seems like an even worse proposition, for the above reasons.

Help me understand, please.

Have you read my proposal? It's in the message posted by me to this thread at 12:31 PM today. My main motivation in proposing it is to give the user complete control over the Python environment that is in their path -- which is not easy to do on Debian/Ubuntu at the moment -- by giving the Python utilities and packages that OS-related functions depend on a completely insular Python environment that the OS can manage however it sees fit. In my view, both as a developer and a user, but especially as a developer, it would make life easier. Steve