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From: Hyman Rosen <hyrosen@mail.com>
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Subject: Re: Question about OO programming in Ada
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Robert I. Eachus wrote:
> Ah, I think I get it.  In C there are many occasions where a function 
> will return a heap object, and it is up to the caller to free the 
> memory.  The returned value can be a copy of the original pointer, so in 
> C it is relatively common to free a copy of the original heap pointer. 
> That may be what is confusing Hyman.

I'm confused about whether I'm confused :-)

Anyway, C++ doesn't set a pointer variable to null when you free its contents.
Since you should be doing this in destructors most of the time, it doesn't matter,
because the pointer variable will very shortly not exist.

Now, as I said, in C++ sometimes objects will delete themselves:
     struct A {
         int refcount;
         void decr() { if (--refcount == 0) delete this; }
         // etc.
     };