burntsushi

joined 1 year ago
[–] burntsushi@programming.dev 7 points 2 months ago (1 children)

I'm on the uv team. I am quite partial to this approach as well. Alas, it's difficult culturally to pull this off in a pre-existing ecosystem. And in the case of Python at least, it's not totally clear to me that it would avoid the need for solving NP hard problems. See my other comment in this thread about simplifying PEP 508 marker expressions.

Other than avoiding needing a SAT solver to resolve dependencies, the other thing I like about Go's approach is that it makes it very difficult to "lie" about the dependencies you support. In a maximal environment, it's very easy to "depend" on foo 1.0 but where you actually need foo 1.1 without issues appearing immediately.

[–] burntsushi@programming.dev 8 points 2 months ago

Interestingly, dependency resolution is not the only NP hard problem uv tries to solve. During development, it also became clear that we needed some way to simplify PEP 508 marker expressions and ask questions like, "are these marker expressions disjoint?"

See: https://github.com/astral-sh/uv/blob/72bd12716225ae48d1e46ec6254d7daf134bdc94/crates/pep508-rs/src/marker/algebra.rs

[–] burntsushi@programming.dev 5 points 2 months ago

uv 0.3 introduces a cross platform lock file: https://docs.astral.sh/uv/concepts/projects/#lockfile

More precise details on the compatibility of uv pip with pip are documented here: https://docs.astral.sh/uv/pip/compatibility/

[–] burntsushi@programming.dev 3 points 1 year ago

Both Perl and Python use backtracking regex engines and are thus susceptible to similar problems as discussed in the OP.