why is there no class (static) methods in Python ?

Michael Lunnay mlunnay at ihug.com.au
Mon Jun 18 08:36:11 CEST 2001


why do you need it as part of the class, if it is related to the class just
have it in the same module so you can do:

import foo

x = foo.foo()
print foo.staticfunction()

Michael

"Richard Gruet" <rgruet at intraware.com> wrote in message
news:3B2D6669.7DEFD13F at intraware.com...
> Martin,
>
>
> Martin von Loewis wrote:
>
> > Richard Gruet <rgruet at intraware.com> writes:
> >
> > > I  (and other people on the Python french mail list) wonder  why there
> > > are no class (static) methods in Python. You cannot define a really
> > > unbounded (ie to an instance) method within the namespace of a class.
> >
> > First of all, you *can* define such a thing if you absolutely want, see
> >
> > http://www.python.org/doc/FAQ.html#4.84
> >
>
> Thanx for the info. But the FAQ confirms that there is no way to define
easily
> a class method. What is recommended (define a module fct) is already what
I
> use.
>
> > > It's not natural nor elegant to have to create an instance to call a
method
> > which is not related to a particular instance. We would like to be able
to
> > write things like:
> > >
> > > class C:
> > >     def staticFoo(x): print x
> > >
> > > C.staticFoo(1)
> >
> > I'd like to question why you want to do this. Isn't it much better to
write
> >
> > class C:
> >   pass
> >
> > def staticFoo(x):
> >   print x
> >
> > I.e. what has class C to do with staticFoo?
>
> Of course, my example is fictitious and was only intended to show the
desired
> syntax. But the reason to choose to define a function as a class method
rather
> than a mere (static) function is -obviously- when this function is closely
> related to the class itself, not to one of its instances. Some languages
like
> smalltalk even define classes as instances of metaclasses, which makes
sense.
> Then you can see class methods like methods of instances that are actually
> classes.
> In fact, constructors (and destructors) are class methods, not instance
> methods, but they are handled specially in the language so they appear as
> instance methods..
>
> Typical examples of class methods:
> loadInstanceFromStream(aStream)    # Create an instance from its
persistent
> state read on a stream
> getInstanceCount()                            # returns the number of
instances
> of this class
> getInstanceList()                                # returns the list of
> instances of this class
> getClassName()  or getAnyInfoOntheClass() ......
>
>
> Richard
>
>





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