Eugene Toder added the comment: There's a similar issue with replace() methods on date/time/datetime classes. They create instances of derived types without calling derived __new__/__init__, thus potentially leaving those uninitialized.
>>> from datetime import date >>> class D(date): ... def __init__(self, y, m, d): ... self.y = y >>> D(2016,1,1).y 2016 >>> D(2016,1,1).replace(2015).y Traceback (most recent call last): File "<stdin>", line 1, in <module> AttributeError: 'D' object has no attribute 'y' ---------- nosy: +eltoder _______________________________________ Python tracker <rep...@bugs.python.org> <http://bugs.python.org/issue23640> _______________________________________ _______________________________________________ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
