range(len(list)) or enumerate(list)? [duplicate]

by

Some quick timing runs seem to give the 2nd option using range() a slight edge over enumerate():

timeit a = [f(n) for n, _ in enumerate(mlist)]
10000 loops, best of 3: 118 us per loop

timeit a = [f(n) for n in range(len(mlist))]
10000 loops, best of 3: 102 us per loop

and just for fun using xrange() (Python v2.7.2)

timeit a = [f(n) for n in xrange(len(mlist))]
10000 loops, best of 3: 99 us per loop

I would favor readable code first, then using xrange() if available (i.e., Pre-Python v 3.x), followed by range() and enumerate().

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