On May 8, 8:46 pm, Steven D'Aprano <st...@remove-this- cybersource.com.au> wrote: > On Sat, 08 May 2010 12:15:22 -0700, Wolfram Hinderer wrote: > > On 8 Mai, 20:46, Steven D'Aprano <st...@remove-this- cybersource.com.au> > > wrote: > > >> def get_leading_whitespace(s): > >> t = s.lstrip() > >> return s[:len(s)-len(t)] > > >> >>> c = get_leading_whitespace(a) > >> >>> assert c == leading_whitespace > > >> Unless your strings are very large, this is likely to be faster than > >> any other pure-Python solution you can come up with. > > > Returning s[:-1 - len(t)] is faster. > > I'm sure it is. Unfortunately, it's also incorrect. > > >>> z = "*****abcde" > >>> z[:-1-5] > '****' > >>> z[:len(z)-5] > > '*****' > > However, s[:-len(t)] should be both faster and correct.
Unless len(t) == 0, surely? -- Mark -- http://mail.python.org/mailman/listinfo/python-list
