[Tutor] Re: How do you share a method (function) among several objects?

[Liam Clarke]

You could a real generic superclass for the classes, it only needs to
contain that one function.

Personally, I see nothing wrong with chucking one function in a module
on it's own, it's whatever works for you. You could create a class for
it also, and give each of the other classes an instance of that
function's class.

Regards, 

Liam Clarke


On Sun, 27 Feb 2005 20:20:19 +0200, Xif <xifxif at gmail.com> wrote:
> Javier Ruere wrote:
> 
> > Xif wrote:
> >
> >> Hello
> >>
> >> There are several different objects. However, they all share the same
> >> function.
> >>
> >> Since they are not the same or similar, it's not logical to use a
> >> common superclass.
> >>
> >> So I'm asking, what's a good way to allow those objects to share that
> >> function?
> >>
> >> The best solution I've found so far is to put that function in a
> >> module, and have all objects import and use it. But I doubt that's a
> >> good use-case for modules; writing and importing a module that contains
> >> just a single function seems like an abuse.
> >>
> >> Thanks,
> >> Xif
> >
> >
> >   Could you give an example?
> >
> > Javier
> >
> > _______________________________________________
> > Tutor maillist  -  Tutor at python.org
> > http://mail.python.org/mailman/listinfo/tutor
> >
> > +++++++++++++++++++++++++++++++++++++++++++
> > This Mail Was Scanned By Mail-seCure System
> > at the Tel-Aviv University CC.
> >
> Sure, I can describe my particular case.
> 
> It's a program that retrieves / updates Microsoft Excel spreadsheet data.
> 
> There are two major classes:
> 
> 1) an Excel class, that represents of the whole Excel program
> 2) a Cells class, that abstracts retrieval  and editing of cells.
> 
> Both classes use a function called getCells() as part of their
> __getitem__() methods.
> 
> getCells() parses the __getitem__() call arguments, and returns an
> iterator over the appropriate cells.
> 
> The difference between the 2 classes is that a Cells instance just
> converts the generator into a list and returns it:
> 
> #<code>
> return list(getCells(self.sheet, cells))
> #</code>
> 
> while an Excel instance returns the values of the cells:
> 
> #<code>
> return [cell.Value for cell in getCells(self.sheet, cells)]
> #</code>
> 
> As you can see, both use the getCells() function.
> 
> So my question is, where is the best way to put it so instances of both
> classes can use it?
> 
> Xif
> _______________________________________________
> Tutor maillist  -  Tutor at python.org
> http://mail.python.org/mailman/listinfo/tutor
> 


-- 
'There is only one basic human right, and that is to do as you damn well please.
And with it comes the only basic human duty, to take the consequences.