Re: what does metaclass mean?
Re: what does metaclass mean?
- Subject: Re: what does metaclass mean?
- From: Ben Dougall <email@hidden>
- Date: Tue, 1 Jul 2003 20:51:45 +0100
On Tuesday, July 1, 2003, at 08:25 pm, Thomas Finley wrote:
On Tuesday, July 1, 2003, at 12:23 PM, Ben Dougall wrote:
about the objective-c pdf. bit confused on what the isa pointer
points to when it's in a class structure. more specifically i don't
know what metaclass means.
A class's class is a metaclass. When you send a message to an object,
it looks in its isa (its class definition) to find the method it
should use. When you send a message to a class, it ALSO looks in the
class's isa (its class, also called a metaclass) to find the method it
should use.
Here's what I remember to help me out: A class of an object is a
class, a class of a class is a metaclass, and the class of a metaclass
is also a metaclass. (She sells sea shells. :) )
yup, that sentence makes it very clear. just what i was after.
With this stuff in mind, your quote from the definition should make
more sense.
thanks very much for your reply Thomas.
it crossed my mind that that's what it might be, but the fact that
super_class is a class's second structure variable / field made me
think otherwise.
so the isa and super_class pointers just happen to be two pointers
pointing to the same thing when it's a class and not the root class. (i
did find out that when root class: isa points to itself and super_class
is NULL).
thanks.
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