Getting rid of virtual environments with a better dependency system

[j c]

Hello all,

I don't know if this suggestion is missing some point, or it's part of something already proposed.

In a professional environment, we've came to a point in which most people use virtual environments or conda environments to avoid "polluting a global environment".

However, I think that's a problem with the default behaviour of the module management in Python. A nice default behaviour would be to search for a requirements.txt file in the same directory as __file__, and use the newest version of every module that matches the constraints. If no requirements where given, the newest version already installed could be used. That would require allowing multiple versions of the same module to be downloaded.

I already anticipate some problems: increased disk usage for people that are not using virtual environments, the possibility of breaking changes for scripts with no constraints over a module (so that if a different module download a newer version, both would be using it), and of course the hassle of a completely new default behaviour that would require a transition in many codebases.

That there are other solutions to the problem, such as forcing the usage of semantic versioning, but that's a bit utopic. But still, I believe it would pay off in terms of time saved in environment installing and switching. Also, it's a good step in the path to integrating pip as something closer to the Python core.

What's your opinion, is the effort required too big for the returns? Do you think other problems may arise?