[Python-Dev] string find(substring) vs. substring in string

Mike Brown mike at skew.org
Wed Feb 16 21:34:16 CET 2005

Fredrik Lundh wrote:
> any special reason why "in" is faster if the substring is found, but
> a lot slower if it's not in there?

Just guessing here, but in general I would think that it would stop searching 
as soon as it found it, whereas until then, it keeps looking, which takes more 
time. But I would also hope that it would be smart enough to know that it 
doesn't need to look past the 2nd character in 'not the xyz' when it is 
searching for 'not there' (due to the lengths of the sequences).

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