Re: pointers in objective-c?

FROM : Glenn English
DATE : Fri Aug 01 21:10:22 2008

Wayne Shao wrote:
> It seems that every object is a pointer in the sample code I have
> seen.  Is there any distinction between an object and its pointer?
>
> In C++,  C* c; would be an uninitialized pointer. But the following
> line will creates an object with the constructor C().
>
> C c;
>
> It seems that there is no such equivalent syntax in Objective-C.
> objects are created either from factory pattern or  [[A alloc]
> someInitMethod ....];
> so, is it possible to write?
>
> NSString a;
> NSNumber b;


Sure. And it'll even compile. But you'd better not try to do much with
them:-)

<my understanding>

Objects in o-c are just plain old structs. And to get to them, you have
to have a pointer.

And the C++ syntax you refer to doesn't exist in o-c. At least it
doesn't do what it does in C++.

So C* c is indeed an uninitialized pointer to a C, just like it says it
is. And C c declares a struct of type C that you can't do anything with,
also just like it says.

C* c = [C new] (or equivalent) is the way do some useful work...

</my understanding>

--
Glenn English
<email_removed>