Home Original page

[Python-Dev] Usage of += on strings in loops in stdlib

Christian Tismer tismer at stackless.com
Wed Feb 13 15:34:06 CET 2013 
On 13.02.13 15:27, Amaury Forgeot d'Arc wrote:
>
> 2013/2/13 Lennart Regebro <regebro at gmail.com <mailto:regebro at gmail.com>>
>
>     On Wed, Feb 13, 2013 at 1:10 PM, Serhiy Storchaka
>     <storchaka at gmail.com <mailto:storchaka at gmail.com>> wrote:
>     > I prefer "x = '%s%s%s%s' % (a, b, c, d)" when string's number is
>     more than 3
>     > and some of them are literal strings.
>
>     This has the benefit of being slow both on CPython and PyPy. Although
>     using .format() is even slower. :-)
>
>
> Did you really try it?
> PyPy is really fast with str.__mod__, when the format string is a 
> constant.
> Yes, it's jitted.

How about the .format() style: Is that jitted as well?
In order to get people to prefer .format over __mod__,
it would be nice if PyPy made this actually _faster_ :-)

-- 
Christian Tismer             :^)   <mailto:tismer at stackless.com>
Software Consulting          :     Have a break! Take a ride on Python's
Karl-Liebknecht-Str. 121     :    *Starship* http://starship.python.net/
14482 Potsdam                :     PGP key -> http://pgp.uni-mainz.de
phone +49 173 24 18 776  fax +49 (30) 700143-0023
PGP 0x57F3BF04       9064 F4E1 D754 C2FF 1619  305B C09C 5A3B 57F3 BF04
       whom do you want to sponsor today?   http://www.stackless.com/

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-dev/attachments/20130213/85fb58ea/attachment.html>
More information about the Python-Dev mailing list