Crate pyenum 

pyenum

Expose Rust enum types to Python as genuine enum.Enum subclasses via PyO3 — #[derive(PyEnum)], functional-API class construction, a per-interpreter cache, and IntoPyObject / FromPyObject conversion plumbing generated by the derive.

Scope

• Unit-variant enums only; tuple / struct / generic / lifetime-parameterised enums are rejected at compile time.
• Five Python enum bases are selectable: Enum (default), IntEnum, StrEnum, Flag, IntFlag.
• Rust variant names are passed through unchanged (Python member name == Rust identifier).
• The Python class is constructed exactly once per interpreter and cached via pyo3::sync::PyOnceLock.
• PyO3 0.28, CPython 3.11+.
• Free-threaded (--disable-gil) Python, module reload, and sub-interpreter finalisation are out of scope.

Structs

PyEnumSpec

Static metadata emitted by #[derive(PyEnum)] for each derived enum.

Enums

PyEnumBase

Python enum base type selector.

VariantLiteral

A single variant’s declared value, ready to be materialised into a Python-side (name, value) tuple for the functional enum.* constructor.

Traits

PyEnumTrait

Bridge between a #[derive(PyEnum)] Rust type and its cached Python class.

PyModuleExt

Extension-method form of add_enum — m.add_enum::<T>()? inside a #[pymodule] is the idiomatic call site.

Functions

add_enum

Register the Python class for T onto module under T::SPEC.name.

Derive Macros

PyEnum

Derive a pyenum::PyEnum implementation for a unit-variant Rust enum.