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konsti 0dd4d017e3 Link to Dependency specifiers instead of PEP 508 (#8411 ) The canonical source is https://packaging.python.org/en/latest/specifications/dependency-specifiers/, not PEP 508 anymore, so we should link there and use the new name.		2024-10-21 14:43:38 -04:00
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src	Link to Dependency specifiers instead of PEP 508 (#8411 )	2024-10-21 14:43:38 -04:00
Cargo.toml	chore: Move all integration tests to a single binary (#8093 )	2024-10-11 16:41:35 +02:00
Changelog.md	Add `uv-` prefix to all internal crates (#7853 )	2024-10-01 20:15:32 -04:00
License-Apache	Add `uv-` prefix to all internal crates (#7853 )	2024-10-01 20:15:32 -04:00
License-BSD	Add `uv-` prefix to all internal crates (#7853 )	2024-10-01 20:15:32 -04:00
Readme.md	Link to Dependency specifiers instead of PEP 508 (#8411 )	2024-10-21 14:43:38 -04:00

Readme.md

Dependency specifiers (PEP 508) in Rust

A library for dependency specifiers, previously known as PEP 508.

Usage

use std::str::FromStr;
use pep508_rs::Requirement;

let marker = r#"requests [security,tests] >= 2.8.1, == 2.8.* ; python_version > "3.8""#;
let dependency_specification = Requirement::from_str(marker).unwrap();
assert_eq!(dependency_specification.name, "requests");
assert_eq!(dependency_specification.extras, Some(vec!["security".to_string(), "tests".to_string()]));

Markers

Markers allow you to install dependencies only in specific environments (python version, operating system, architecture, etc.) or when a specific feature is activated. E.g. you can say importlib-metadata ; python_version < "3.8" or itsdangerous (>=1.1.0) ; extra == 'security'. Unfortunately, the marker grammar has some oversights (e.g. https://github.com/pypa/packaging.python.org/pull/1181) and the design of comparisons (PEP 440 comparisons with lexicographic fallback) leads to confusing outcomes. This implementation tries to carefully validate everything and emit warnings whenever bogus comparisons with unintended semantics are made.