Python Class use

[Roel Schroeven]

S Borg schreef:
>  Hello,
> 
>  I am running Python on Mac OS X. The interpreter has been great for
> learning the basics, but I would now like to be able to reuse code.
> How do I write reusable code? I have done it "The Java way": write
> the class, and save it to my home directory, then call it from the
> interpreter, here is an example.
> 
> ########my saved file######
> class MyClass:
>   def f(self):
>       return 'calling f from MyClass'
> 
> #######interpreter#########
>>>> x = MyClass()
>>>> (unhelpful error mesages)
> 
> I hope I have clearly explained my problem.

I think so.

Python does this different from Java. One difference is that Python 
allows you to put more than one class in a module (you also don't have 
to put everything in a class; code can live in a module's global 
namespace too). Then, to use code from that module, you have to import 
it with the import statement.

Putting it all together, you could create a file MyModule.py which 
contains the code you mentioned, and then use it like this:

import MyModule

x = MyModule.MyClass()
x.f()

Or you could directly import MyClass into the global namespace like this:

from MyModule import MyClass

x = MyClass()
x.f()

But that's not recommended since it clutters the global namespace and 
makes it more difficult to see which name comes from which module.


-- 
If I have been able to see further, it was only because I stood
on the shoulders of giants.  -- Isaac Newton

Roel Schroeven