metaclass : parse all class once before doing anything else ?

[Laurent Rahuel]

Hi,

I have a much to smart problem for my brain.

Here is the deal :

I got a metaclass named Foo

Then I got two others classes:

class Bar(Foo):
pass

class Baz(Foo):
pass

I know how to add some attrs, methods to Bar and Baz when the module is
loaded but I need to do something more :

Before adding anything to these classes,
1 - I need to parse all defined Foo classes
2 - "sort" them
3 - parse this sorted list to add attrs and methods.

This seems to be really to clever for me ;-(

Any idea ?

Regards,

Laurent.

[Diez B. Roggisch]

Laurent Rahuel schrieb:

I got a metaclass named Foo

I have the impression that you are not talking about a meta-class, but a
normal class here.

Then I got two others classes:

class Bar(Foo):
pass

class Baz(Foo):
pass

I know how to add some attrs, methods to Bar and Baz when the module is
loaded but I need to do something more :

Before adding anything to these classes,
1 - I need to parse all defined Foo classes
2 - "sort" them
3 - parse this sorted list to add attrs and methods.

This seems to be really to clever for me ;-(

Any idea ?

Why do you want to do this? It is in that way not possible - python has
no preprocessing step that would allow this.

I suggest you explain to us what you are after here, and then we might
come up with a solution.

Diez

[Paddy]

Laurent Rahuel wrote:

Hi,

I have a much to smart problem for my brain.

Here is the deal :

I got a metaclass named Foo

Then I got two others classes:

class Bar(Foo):
pass

class Baz(Foo):
pass

I know how to add some attrs, methods to Bar and Baz when the module is
loaded but I need to do something more :

Before adding anything to these classes,
1 - I need to parse all defined Foo classes
2 - "sort" them
3 - parse this sorted list to add attrs and methods.

This seems to be really to clever for me ;-(

Any idea ?

Regards,

Laurent.

I, like Diez am unsure of why you would need what you have asked for,
but maybe this will help.

You can keep track of all instances of a class by this kind of thing:

>>class C1(object):

.... inst = []
.... def __init__(self):
.... self.inst.append(self)
....

>>i1 = C1()
i2 = C1()
print i1,i2

<__main__.C1 object at 0x0128C970<__main__.C1 object at 0x0128CA50>

>>print C1.inst

[<__main__.C1 object at 0x0128C970>, <__main__.C1 object at
0x0128CA50>]

>>>

[gene tani]

Paddy wrote:

Laurent Rahuel wrote:

Laurent.

I, like Diez am unsure of why you would need what you have asked for,
but maybe this will help.

You can keep track of all instances of a class by this kind of thing:

>class C1(object):

... inst = []
... def __init__(self):
... self.inst.append(self)
...

or list all subclasses with

print LaurentsPutativeMetaClass.__subclasses__()

me 3 for: not clear what you're getting at