> I'm stumped. This silly bit of code doesn't work. I expect the > output to be 8, not 18. What am I missing? > > class Under10(int): > def __init__(self, number): > number %= 10 > int.__init__(self, number)
marilyn, i agree with most of the earlier replies... you need to use __new__() instead of __init__() in order to "tweak" the original value before the instance of the immutable object is created. once it's "frozen," you're stuck. note that __new__() is a class method, so you'll need a variable for the class (instead of self for the instance). also recall that __init__() is (the 1st method) called *after* an instance has been created, which for you, would be too late. in practice, i don't think __init__() is ever used for deriving from immutable types. does anyone have a counterexample? (since i know you've been reading Core Python, you can take a look at my example of subclassing an immutable type on p.552.) :-) cheers, -- wesley - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - "Core Python Programming", Prentice Hall, (c)2007,2001 http://corepython.com wesley.j.chun :: wescpy-at-gmail.com python training and technical consulting cyberweb.consulting : silicon valley, ca http://cyberwebconsulting.com _______________________________________________ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor