Warp wrote:
>   'union' in C is basically a construct which exists to save some bytes
> of memory in some rare circumstances.

I have also seen it used for typecasting, but nowadays I think casting the 
address of the thing to the "wrong" pointer type and then indirecting it 
gets used more.  I.e.;  { long x = ...; float f = *(float*)&x; }

>   As for removing null pointers, that would present problems of its own.
> Null pointers in languages like C, C++ and Java are often used for useful
> things. 

I think the way to think of it is that a pointer that can be null is a 
different type than a pointer that can't be null, and you have to do the 
equivalent of a dynamic_cast<> from a nullable pointer to a non-nullable 
pointer before you can indirect thru it.

Of course, if your language wasn't lame, you'd be able to just say
    if (x != null) y = *x;
and the compiler would use typestate or something to let that go, whereas 
without the "if (x != null)" on the front, it would complain that maybe *x 
is indirecting thru null.

The problem isn't that pointers might be null. The problem is that someone 
might indirect thru a null (or otherwise uninitialized) pointer without 
knowing it.

>   In Objective-C you usually don't have to check for null pointers. 

That's the other way to handle it. Or to throw an exception which you can 
catch.  The Obj-C way certainly sounds more ... PHPish. ;-)

-- 
Darren New, San Diego CA, USA (PST)
   Serving Suggestion:
     "Don't serve this any more. It's awful."

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