Original code copyright (C) 2009-2022 Rudolf Cardinal (

This file is part of cardinal_pythonlib.

Licensed under the Apache License, Version 2.0 (the “License”); you may not use this file except in compliance with the License. You may obtain a copy of the License at

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Rate-limiting functions.

cardinal_pythonlib.rate_limiting.rate_limited(max_per_second: int | float | None) Callable[[Callable[[...], Any]], Callable[[...], Any]][source]

Returns a function that rate-limits another function to the specified frequency. Can be used as a decorator, e.g.

from cardinal_pythonlib.rate_limiting import rate_limited

def do_something_max_2hz():

for i in range(10):

or dynamically:

from cardinal_pythonlib.rate_limiting import rate_limited

def do_something():

limited = rate_limited(2)(do_something)
for i in range(10):

max_per_second – maximum number of calls per second to permit, or None for no limit


a function that takes a function argument

Based on, with minor modifications.