On 10月11日, 下午5时30分, ryles <ryle...@gmail.com> wrote: > On Oct 11, 3:04 am, metal <metal...@gmail.com> wrote: > > > > > Environment: > > > PythonWin 2.5.4 (r254:67916, Apr 27 2009, 15:41:14) [MSC v.1310 32 bit > > (Intel)] on win32. > > Portions Copyright 1994-2008 Mark Hammond - see 'Help/About PythonWin' > > for further copyright information. > > > Evil Code: > > > class Foo: > > def __init__(self, *args): > > print args > > > Foo(1, 2, 3) # (1, 2, 3), good > > > class Bar(tuple): > > def __init__(self, *args): > > print args > > > Bar(1, 2, 3) # TypeError: tuple() takes at most 1 argument (3 given) > > > what the heck? I even didn't call tuple.__init__ yet > > When subclassing immutable types you'll want to override __new__, and > should ensure that the base type's __new__ is called: > > __ class MyTuple(tuple): > __ def __new__(cls, *args): > __ return tuple.__new__(cls, args) > __ print MyTuple(1, 2, 3) > > (1, 2, 3) > > Seehttp://www.python.org/download/releases/2.2.3/descrintro/#__new__
That's it. Thank you very much. -- http://mail.python.org/mailman/listinfo/python-list
