paul j3 added the comment: http://bugs.python.org/issue9849 also deals with nargs values. However there the focus is on string values like '1', not whether an integer value can be 0 or <0.
I submitted a patch that moves the nargs testing to a ArgumentParser._check_argument() method. It still depends on _format_args to do the actual testing of nargs. I also make sure that group.add_argument() does this test. Regarding this issue, can nargs=0 or <0? _Store_action objects to 0, not because it causes runtime errors, but because it does not make sense. Code with nargs=-1 runs without error, not consuming a string and returning [], just as a nargs=0 would. In http://bugs.python.org/issue14191 I found it useful to temporarily set nargs=0 to 'turn off' a positional. I would vote for leaving this error message as is: "ValueError: nargs for store actions must be > 0; if you have nothing to store, actions such as store true or store const may be more appropriate" even though the test is actually nargs==0. For normal use the recommendation that nargs>0 makes sense. ---------- nosy: +paul.j3 _______________________________________ Python tracker <rep...@bugs.python.org> <http://bugs.python.org/issue16970> _______________________________________ _______________________________________________ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
