paul j3 <ajipa...@gmail.com> added the comment:
This is a consequence of Python's own definition of append vs extend In [730]: alist = [] In [731]: alist.append('astring') In [732]: alist Out[732]: ['astring'] In [733]: alist.extend('astring') In [734]: alist Out[734]: ['astring', 'a', 's', 't', 'r', 'i', 'n', 'g'] In [735]: alist.extend(['astring']) In [736]: alist Out[736]: ['astring', 'a', 's', 't', 'r', 'i', 'n', 'g', 'astring'] Normally 'add_argument' doesn't check for valid parameters, but some Action subclasses do their own checking, 'extend' inherits the nargs==0 test from 'append'. (extend just modifies the __call__, not the __init__ method. But I wonder, was this situation discussed in the original bug/issue? ---------- _______________________________________ Python tracker <rep...@bugs.python.org> <https://bugs.python.org/issue40365> _______________________________________ _______________________________________________ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com