bearcheck

Tiny extension to beartype, which allows inline type assertion and narrowing similar to check_type from typeguard.

Using bearcheck() is faster and safer than check_type(), since it leverages the incredibly fast beartype library for type checking, and allows specifying the exact return type.

Usage

from bearcheck import bearcheck, Check

var = bearcheck("a", Check[Literal["a", "b"]])
reveal_type(var)  # Type of "var" is "Literal['a', 'b']"

.. as opposed to ..

from typeguard import check_type

var = check_type("a", Literal["a", "b"])
reveal_type(var)  # Type of "var" is "Any"

type_check() returns Any if the type hint is not primitive, a common pitfall!