[Python-Dev] transitioning from % to {} formatting

Vinay Sajip vinay_sajip at yahoo.co.uk
Fri Oct 2 00:12:03 CEST 2009

James Y Knight <foom <at> fuhm.net> writes:

> Using containment instead of inheritance makes sure none of the  
> *other* operations people do on strings will appear to work, at least  
> (substring, contains, etc). I bet explicitly calling str() on a format  
> string is even more rare than attempting to do those things.

Actually, logging calls str() on the object passed as the first argument in a
logging call such as logger.debug(), which can either be a format string or an
arbitrary object whose __str__() returns the format string.


Vinay Sajip

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