matplotlib/matplotlib — pull request #1493 by minrk (2012-11-13 19:58:11+00:00)
Title: check `ret is False` in Timer._on_timer

The docstring states:

> Functions can return False if they should not be called any more.

Cleanup commit 2f11dee changed this logic so any return value whose boolean interpretation is False (e.g. None) would be unregistered.

This restores the logic to check only for explicit False (not None, not 0, etc.).

fixes #1492