Warp wrote:
> Darren New <dne### [at] sanrrcom> wrote:
>> Warp wrote:
>>>     IntegerOrFloat* ptr = whatever;
> 
>> That's a pointer to a struct. :-)
> 
>   A union is not a struct. 

My bad. I understood, I just mispoke.

> The 'ptr' truely points directly to either an
> integer or a float, 

No, it points to the union. The integer and the float are both at the 
same *address*, but the pointer points to a *union*. :-)

Consider the difference between "pointer arithmetic" and "address 
arithmetic". If ptr points to an integer, then ptr++ should change its 
address by sizeof(int), right?

Again, it's nitpicking, but it's the kind of language-lawyering that 
language designers babble about.

> at the exact same memory location. There's no need
> to calculate memory offsets.

Right. That's *address* arithmetic, tho. You can have different types of 
pointers all pointing to the same address, *because* the difference 
between "pointer" and "address" is whether it has a type. (At least in 
most language design discussions.)

>> You can implement private methods that only the class can call and which 
>> are invisible to any code not in the class defining the method, if 
>> that's what you mean.  You can even put it in a separate file all by itself.
> 
>   If that's so, what's this talk about C# forcing you to implement everything
> inline? I thought that meant you *can't* implement any part of a class in
> a separate file.

Err, no. It's called a "partial class". I believe perhaps the first 
version of C# didn't have that?

// File A1.cs
partial class A {
   void alpha(...) { ... }
}

// File A2.cs
partial class A {
   void beta(...) { ... }
}

As I said, mostly used for code generators to stay out of your way.



-- 
   Darren New / San Diego, CA, USA (PST)
     "That's pretty. Where's that?"
          "It's the Age of Channelwood."
     "We should go there on vacation some time."

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