Tag class final

Tag

python docstring

A representation of the tag triple for a wheel.

Instances are considered immutable and thus are hashable. Equality checking is also supported.

python source

class Tag:
    """
    A representation of the tag triple for a wheel.

    Instances are considered immutable and thus are hashable. Equality checking
    is also supported.
    """

    __slots__ = ["_interpreter", "_abi", "_platform", "_hash"]

    def __init__(self, interpreter: str, abi: str, platform: str) -> None:
        self._interpreter = interpreter.lower()
        self._abi = abi.lower()
        self._platform = platform.lower()
        # The __hash__ of every single element in a Set[Tag] will be evaluated each time
        # that a set calls its `.disjoint()` method, which may be called hundreds of
        # times when scanning a page of links for packages with tags matching that
        # Set[Tag]. Pre-computing the value here produces significant speedups for
        # downstream consumers.
        self._hash = hash((self._interpreter, self._abi, self._platform))

    @property
    def interpreter(self) -> str:
        return self._interpreter

    @property
    def abi(self) -> str:
        return self._abi

    @property
    def platform(self) -> str:
        return self._platform

    def __eq__(self, other: object) -> bool:
        if not isinstance(other, Tag):
            return NotImplemented

        return (
            (self._hash == other._hash)  # Short-circuit ASAP for perf reasons.
            and (self._platform == other._platform)
            and (self._abi == other._abi)
            and (self._interpreter == other._interpreter)
        )

    def __hash__(self) -> int:
        return self._hash

    def __str__(self) -> str:
        return f"{self._interpreter}-{self._abi}-{self._platform}"

    def __repr__(self) -> str:
        return f"<{self} @ {id(self)}>"