adding a static class to another class

[Bruno Desthuilliers]

Nathan Harmston a écrit :
> HI,
> 
> I m trying to start an api in a similar way to the djangic way of
> Class.objects.all(). Ie objects is a "Manager" class.
> 
> So:
> 
> class Foo(object):
>    def __init__(self):
>         self.test = "NEE"
> 
> class Manager(object):
>     def __init__(self):
>         pass
>    def all(self):
>        return "COCONUTS"
> 
> Because of how some of the code is set up I cant use
> metaclasses........so I try to use a decorator:
> 
> def addto(instance):
>     def decorator(f):
>         import new
>         f = new.instancemethod(f, instance, instance.__class__)
>         setattr(instance, "objects", f)
>         return f
>     return decorator
> 
> class Manager(object):
>     @addto(Foo)
>     def __init__(self):
>        .............
> 
> however this only binds the init method to the Foo.objects, so not
> what I want. 

Indeed.

> If I try using classmethod...then it just says the
> Foo.objects doesnt exist.

You mean decorating Manager.__init__ with classmethod ???

I may be wrong, but I suspect you don't have a clear idea of what you're 
doing here.

> Does anyone have any ideas how I can accomplish this using decorators?

Yes : don't use a decorator !-)

Instead of asking for how to implement what you think is the solution, 
you might be better explaining the problem you're trying to solve.

> And also preventing more than one Manager instance instantiated at one
> time.

Q&D:

class Singleton(object):
     def __new__(cls):
         if not hasattr(cls, '_inst'):
             cls._inst = object.__new__(cls)
         return cls._inst
	

Same remark as above...