STINNER Victor added the comment: > The code is now using the heavily optimized findchar() function.
I compared performances of the two methods: dummy loop vs find. Results with a string of 100,000 characters: * Replace 100% (rewrite all characters): find is 12.5x slower than a loop * Replace 50%: find is 3.3x slower * Replace only 2 characters (0.001%): find is 10.4x faster In practice, I bet that the most common case is to replace only a few characters. Replace all characters is a rare usecase. Use attached "unicode.patch" on Python 3.4 with the following commands to reproduce my benchmark: python -m timeit -s "a='a'; b='b'; text=a*100000" "text.replace(a, b)" python -m timeit -s "a='a'; b='b'; text=(a+' ')*(100000//2)" "text.replace(a, b)" python -m timeit -s "a='a'; b='b'; text=a+' '*100000+a" "text.replace(a, b)" -- An option is to use the find method, and then switch to the dummy loop method if there are too much characters to replace. I don't know if it's necessary to develop such complex algorithm. It would be better to have a benchmark extracted from a real world application like a template engine. ---------- keywords: +patch Added file: http://bugs.python.org/file27521/unicode.patch _______________________________________ Python tracker <rep...@bugs.python.org> <http://bugs.python.org/issue16061> _______________________________________ _______________________________________________ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
