Wouter Bolsterlee added the comment: Thanks Raymond, that is exactly what I had in mind (see my previous comment). Here's a slightly cleaned up version of the patch (stylistic/PEP8 cleanups), with some benchmarks included below.
In case the two longest iterators have about the same size, no performance difference can be measured: $ ./python -m timeit -s 'from heapq import merge' 'for x in merge([], [], [1], range(100), range(100)): pass' Without patch: 10000 loops, best of 3: 71.2 usec per loop 10000 loops, best of 3: 71.9 usec per loop 10000 loops, best of 3: 71.7 usec per loop With patch: 10000 loops, best of 3: 71.4 usec per loop 10000 loops, best of 3: 76.7 usec per loop 10000 loops, best of 3: 72.1 usec per loop As expected, the performance gain is very significant in case one of the iterators is much longer than the others: $ python -m timeit -n 100 -s 'from heapq import merge' 'for x in merge([], [], [1], range(100), range(100000)): pass' Without path: 100 loops, best of 3: 27.8 msec per loop 100 loops, best of 3: 26.9 msec per loop 100 loops, best of 3: 27.7 msec per loop With patch: 100 loops, best of 3: 6.26 msec per loop 100 loops, best of 3: 6.28 msec per loop 100 loops, best of 3: 6.03 msec per loop ---------- Added file: http://bugs.python.org/file31726/merge3.diff _______________________________________ Python tracker <rep...@bugs.python.org> <http://bugs.python.org/issue18962> _______________________________________ _______________________________________________ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
