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Re: id vs cast

I assume you don't have ownership of that function? Because if you know, as you seem to, that it returns a pointer of a very specific type, it seems perverse to declare it as a function returning (void > *).


I do not have ownership of the function.


void * thePointer; // known to point to a TheClass
TheClass * myObject;
id alsoMyObject;

myObject = (TheClass *) thePointer; // A
alsoMyObject = (id) thePointer; // B

Both A and B will compile to a single load of a register. There's no run-time difference.

What I have used successfully is your "A" example and the following:
id alsoMyObject = thePointer;

It is this 2nd way I was able to use the pointer (not the "B" you have shown) that I was curious about. Is it correct to do it in this manner...and is it any faster? From your post it sounds like the "A" example is already extremely fast...so I am guessing there is no need to do it any other way.
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