cacheprop 0.1.0

Typed cached property decorator with async support

cacheprop

A typed cached property decorator with async support.

Why?

• Makes caching of time or computation-expensive properties quick and easy.
• Provides proper type checking via PEP 695 generic syntax (class cacheprop[T]).
• Works with both sync and async methods — the return value is automatically awaited for async functions.
• Preserves __doc__ and __annotations__ from the wrapped function.

Installation

pip install cacheprop

Requires Python 3.12+ (uses PEP 695 type parameter syntax).

Usage

Sync methods

from cacheprop import cacheprop


class MyClass:
    @cacheprop
    def expensive(self) -> str:
        return heavy_computation()


obj = MyClass()
print(obj.expensive)  # calls heavy_computation(), caches result
print(obj.expensive)  # returns cached value, no call

Async methods

class MyAsyncClass:
    @cacheprop
    async def fetch_data(self) -> dict:
        return await http_get("https://example.com/api")


async def main():
    obj = MyAsyncClass()
    data1 = await obj.fetch_data  # awaits and caches
    data2 = await obj.fetch_data  # returns cached value, no await needed

Reusing an existing function

def get_absolute_url(self):
    return f"/items/{self.id}"


class Item:
    url = cacheprop(get_absolute_url)

Type checking

The generic parameter T lets type checkers infer the return type:

@cacheprop
def size(self) -> int:
    return len(self.data)

reveal_type(obj.size)  # int (not object or Any)

License

0BSD