[Python-Dev] Status regarding Old vs. Advanced String Formating (original) (raw)

Terry Reedy tjreedy at udel.edu
Fri Feb 24 20:52:09 CET 2012

On 2/24/2012 11:41 AM, Benjamin Peterson wrote:

2012/2/24 Tshepang Lekhonkhobe<tshepang at gmail.com>:

Hi,

I was of the thought that Old String Formatting |"%s" % foo| was to be phased out by Advanced String Formatting |"{}.format(foo)|. I however keep seeing new code committed into the main VCS using the old style. Is this okay? Is there a policy? I ask also because I expect CPython to lead by example. Using either is fine I think. It doesn't hurt anyone to have old string formatting around for a long time.

It is a burden for some people to learn and remember the exact details of both systems and exactly how they differ. Having both in the stdlib hurts readability for such people. I would prefer that the stdlib only used {} formatting or if not that, that it only used the simple, hard-to-forget forms of % formatting (%s, %d, %f, without elaboration).

-- Terry Jan Reedy

More information about the Python-Dev mailing list