Terry Reedy wrote:
John Arbash Meinel wrote:
So 'for x in s: break' is about 2x faster than next(iter(s)) and 3x faster than (iter(s).next()). I was pretty surprised that it was 30% faster than "for x in s: pass". I assume it has something to do with a potential "else:" statement?
for x in s: pass
iterates through *all* the elements in s and leaves x bound to the arbritrary *last* one instead of the arbitrary *first* one. For a large set, this would be a lot slower, not just a little.
fwiw, I think the use case for this is sufficiently rare that it does not need a separate method just for this purpose.
tjr
The point of my test was that it was a set with a *single* item, and 'break' was 30% faster than 'pass'. Which was surprising. Certainly the difference is huge if there are 10k items in the set. John =:->