[Python-3000] optimizing [x]range (original) (raw)

"Martin v. Löwis" martin at v.loewis.de
Sun Jul 29 21:03:06 CEST 2007

Don't forget the cost in terms of code bloat. Plus, I asked for a patch. Where is it? This is not Santa Claus's email address. You're expected to contribute more than a wish. first off all, that's not the politest way to put it, especially since i have submitted some patches before. second, i've already given a 3-line implementation in python. it would only take two minutes to convert it to C, save the unit tests. third, i'm busy over my head studying of my exams. forth, due to lack of public interest, i might as well withdraw this.

It's not that you were asked to contribute it. Guido just pointed out that, without a patch, it won't get implemented. More so if the patch is as trivial as you expect it to be. We all are under time pressure - I am busy giving exams, for example.

So to your original question "why not optimize it?", there is a very simple answer: there is no ready implementation available.

besides, that's not the point. i'm only saying there's no reason that testing for containment in range objects (which are no longer lists), should be O(N), when it can easily be made O(1) in under 10 lines of C code.

Nothing is easy. Neal Norwitz was working on implementing xrange with longs, and it took an entire week. The patch is still sitting on SF somewhere.

Regards, Martin

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