This was also brought up back in April: https://mail.python.org/pipermail//python-ideas/2016-April/039707.html
It got a few replies from Guido (https://mail.python.org/pipermail//python-ideas/2016-April/039713.html for one of them). It seems the idea got dropped due to problems with making it properly random (practically, the sampling has issues in cases of very large sequences, let along infinite) and performance (either large numbers of calls to random, or copying the sequence, each of which has its own problems). There are also issues with how it should behave on iterables that cannot be re-iterated (eg, random.choice will consume the iterator, and could only be called once safely). Chris On Wed, Nov 30, 2016 at 11:42 AM, Bernardo Sulzbach <mafagafogiga...@gmail.com> wrote: > On 2016-11-30 17:25, Random832 wrote: >> >> Currently these functions fail if the supplied object has no len(). >> There are algorithms for this task that can work on any finite iterator >> (for example, files as a stream of lines), and the functions could fall >> back to these if there is no len(). > > > I like the idea, as long as it does not add too much overhead to currently > existing code. > > It could be a special code path for reservoir sampling (I assume) for both > functions (the first taking only one sample from the stream). > > > -- > Bernardo Sulzbach > http://www.mafagafogigante.org/ > mafagafogiga...@gmail.com > > _______________________________________________ > Python-ideas mailing list > Python-ideas@python.org > https://mail.python.org/mailman/listinfo/python-ideas > Code of Conduct: http://python.org/psf/codeofconduct/ _______________________________________________ Python-ideas mailing list Python-ideas@python.org https://mail.python.org/mailman/listinfo/python-ideas Code of Conduct: http://python.org/psf/codeofconduct/
