Sibylle Koczian a écrit : (snip)
I don't understand at all why I get the same message with this little script: ############################ import datetime class meindatum(datetime.date): def __init__(self, datum): print "meindatum" datetime.date.__init__(self, datum.year, datum.month, datum.day) x1 = datetime.date.today() print repr(x1) x2 = meindatum(x1) print repr(x2) ####################################### Executing this from the command line: s...@elend:~> python /windows/E/LinWin/Python/datum_ableiten.py datetime.date(2009, 3, 25) Traceback (most recent call last): File "/windows/E/LinWin/Python/datum_ableiten.py", line 12, in <module> x2 = meindatum(x1) TypeError: an integer is required s...@elend:~> The print command inside the __init__ method isn't executed, so that method doesn't seem to start at all.
this often happens with (usually C-coded) immutable types. The initializer is not called, only the "proper" constructor (__new__). The following should work (not tested):
class Meindatum(datetime.date): def __new__(self, datum): print "meindatum" return datetime.date(datum.year, datum.month, datum.day) HTH -- http://mail.python.org/mailman/listinfo/python-list