.. Comment: this file is automatically generated by `update_example_docs.py`. It should not be modified manually. .. _example-category-generics: Generics ======== :mod:`tyro`'s understanding of Python's type system includes user-defined parameterized types, which can reduce boilerplate and improve type safety. .. _example-01_generics_py312: Generics (3.12+) ---------------- This example uses syntax introduced in Python 3.12 (`PEP 695 `_). .. note:: If used in conjunction with :code:`from __future__ import annotations`, the updated type parameter syntax requires Python 3.12.4 or newer. For technical details, see `this CPython PR `_. .. code-block:: python :linenos: # 01_generics_py312.py import dataclasses import tyro @dataclasses.dataclass class Point3[ScalarType: (int, float)]: x: ScalarType y: ScalarType z: ScalarType frame_id: str @dataclasses.dataclass class Triangle: a: Point3[float] b: Point3[float] c: Point3[float] @dataclasses.dataclass class Args[ShapeType]: shape: ShapeType if __name__ == "__main__": args = tyro.cli(Args[Triangle]) print(args) .. raw:: html

    $ python ./01_generics_py312.py --help
    usage: 01_generics_py312.py [-h] [OPTIONS]
    
    ╭─ options ───────────────────────────────────────────────╮
    │ -h, --help              show this help message and exit │
    ╰─────────────────────────────────────────────────────────╯
    ╭─ shape.a options ───────────────────────────────────────╮
    │ --shape.a.x FLOAT       (required)                      │
    │ --shape.a.y FLOAT       (required)                      │
    │ --shape.a.z FLOAT       (required)                      │
    │ --shape.a.frame-id STR  (required)                      │
    ╰─────────────────────────────────────────────────────────╯
    ╭─ shape.b options ───────────────────────────────────────╮
    │ --shape.b.x FLOAT       (required)                      │
    │ --shape.b.y FLOAT       (required)                      │
    │ --shape.b.z FLOAT       (required)                      │
    │ --shape.b.frame-id STR  (required)                      │
    ╰─────────────────────────────────────────────────────────╯
    ╭─ shape.c options ───────────────────────────────────────╮
    │ --shape.c.x FLOAT       (required)                      │
    │ --shape.c.y FLOAT       (required)                      │
    │ --shape.c.z FLOAT       (required)                      │
    │ --shape.c.frame-id STR  (required)                      │
    ╰─────────────────────────────────────────────────────────╯

.. _example-02_generics: Generics (Legacy) ----------------- The legacy :py:class:`typing.Generic` and :py:class:`typing.TypeVar` syntax for generic types is also supported. .. code-block:: python :linenos: # 02_generics.py import dataclasses from typing import Generic, TypeVar import tyro ScalarType = TypeVar("ScalarType", int, float) ShapeType = TypeVar("ShapeType") @dataclasses.dataclass(frozen=True) class Point3(Generic[ScalarType]): x: ScalarType y: ScalarType z: ScalarType frame_id: str @dataclasses.dataclass(frozen=True) class Triangle: a: Point3[float] b: Point3[float] c: Point3[float] @dataclasses.dataclass(frozen=True) class Args(Generic[ShapeType]): shape: ShapeType if __name__ == "__main__": args = tyro.cli(Args[Triangle]) print(args) .. raw:: html

    $ python ./02_generics.py --help
    usage: 02_generics.py [-h] [OPTIONS]
    
    ╭─ options ───────────────────────────────────────────────╮
    │ -h, --help              show this help message and exit │
    ╰─────────────────────────────────────────────────────────╯
    ╭─ shape.a options ───────────────────────────────────────╮
    │ --shape.a.x FLOAT       (required)                      │
    │ --shape.a.y FLOAT       (required)                      │
    │ --shape.a.z FLOAT       (required)                      │
    │ --shape.a.frame-id STR  (required)                      │
    ╰─────────────────────────────────────────────────────────╯
    ╭─ shape.b options ───────────────────────────────────────╮
    │ --shape.b.x FLOAT       (required)                      │
    │ --shape.b.y FLOAT       (required)                      │
    │ --shape.b.z FLOAT       (required)                      │
    │ --shape.b.frame-id STR  (required)                      │
    ╰─────────────────────────────────────────────────────────╯
    ╭─ shape.c options ───────────────────────────────────────╮
    │ --shape.c.x FLOAT       (required)                      │
    │ --shape.c.y FLOAT       (required)                      │
    │ --shape.c.z FLOAT       (required)                      │
    │ --shape.c.frame-id STR  (required)                      │
    ╰─────────────────────────────────────────────────────────╯