[Python-3000] Please don't kill the % operator...

Thu Aug 16 17:05:36 CEST 2007

Thanks for the detailed response.
 Guido> Now on to the transition. On the one hand I always planned this
 Guido> to *replace* the old %-formatting syntax, which has a number of
 Guido> real problems: "%s" % x raises an exception if x happens to be a
 Guido> tuple, and you have to write "%s" % (x,) to format an object if
 Guido> you aren't sure about its type; also, it's very common to forget
 Guido> the trailing 's' in "%(name)s" % {'name': ...}.
I was conflating the format string and the % operator in some of my (casual)
thinking. I'm much less married to retaining the % operator itself (that is
the source of most of the current warts I believe), but as you pointed out
some of the format string proposals are pretty scary.
 Guido> I don't know what percentage of %-formatting uses a string
 Guido> literal on the left; if it's a really high number (high 90s), I'd
 Guido> like to kill %-formatting and go with mechanical translation;
 Guido> otherwise, I think we'll have to phase out %-formatting in 3.x or
 Guido> 4.0.
Yow! You're already thinking about Python 4???
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