[Tutor] Calling super classs __init__?
ricaraoz at gmail.com
Wed Mar 19 14:36:29 CET 2008
Luciano Ramalho wrote:
> Nowadays the best practice for invoking a method from all superclasses
> (yes, multiple inheritance) is this:
> class SubClass(BaseClass):
> def __init__(self, t, *args, **kw):
> super(SubClass, self).__init__(*args, **kw)
> # do something with t
> That way you let Python decide which superclasses your SubClass has,
> instead of hard-coding it in several places.
You are actually hard-coding it here too, "class SubClass(BaseClass):"
has "BaseClass" hard-coded. All you do here is hard-code it once instead
> On Tue, Mar 18, 2008 at 9:37 PM, John Fouhy <john at fouhy.net> wrote:
>> On 19/03/2008, Allen Fowler <allen.fowler at yahoo.com> wrote:
>> > I have a super class that accepts many arguments to it's constructor, and a subclass that should define one additional argument.
>> > What's the most "pythonic" way to make this work?
>> class BaseClass(object):
>> def __init__(self, x, y, z, foo='foo'): # whatever
>> # etc
>> class SubClass(BaseClass):
>> def __init__(self, t, *args, **kw):
>> BaseClass.__init__(self, *args, **kw)
>> # do something with t
>> This does mean that the special sub class argument has to come before
>> the base class arguments when you create instances.
>> Whether you call BaseClass.__init__ early or late in the subclass init
>> method could depend on what your classes are doing. Remember, in
>> Python, __init__ only initializes objects, it doesn't create them.
>> It's just another bit of code that you can call whenever you want.
>> Tutor maillist - Tutor at python.org
> Tutor maillist - Tutor at python.org
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