Duncan Booth wrote:
Mr.SpOOn <[EMAIL PROTECTED]> wrote:Now I must pass a and b to the main constructor and calculate them in the classmethods. class foo: def __init__(self, a, b): self.a = a self.b = b @classmethod def from_string(self, ..): ... ... What I mean is: I can't use anymore __init__ as the default constructor, but I always have to specify the way I'm creating my object. Am I right? I'm asking just to be sure I have understood.There is a really big advantage to being explicit in this situation: you no longer have to make sure that all your constructors use a unique set of types. Consider:class Location(object): def __init__(self, lat, long): ... @classmethod def from_city(name): ... @classmethod def from_postcode(name): ...'from_string' is a bad name here for your factory method: you should try to make it clear what sort of string is expected.
One built-in model for .__init__ + .from_data is dict. __init__ can take either one iterable or several keywords. In either case, it gets a set of key:value pairs. .from_keys take a set of keys and an optional value to override None that is matched with all keys.
-- http://mail.python.org/mailman/listinfo/python-list
