Re: Non-null pointers in C/C++?

Angel Tsankov wrote:
> James Kuyper wrote:
....
>> I think that if you had wanted to im****t the C++ concept of
>> references,
>>
> No, I did not wanted to do this and I never did or implied it.

What few advantages your concept of unnullable pointers have, are 
advantages that are shared, and improved upon, by C++ references.

>> that would have had some advantages, possibly enough to
>> make it a good idea.
>>
> Do you suggest that C++ references are not a good idea?!

No, exactly the opposite. I think that they can be useful syntactic 
suger, though they would be less useful as an addition to C than they 
are as part of C++.

>> A C++ reference can be implemented in a way that
>> makes it seem just like syntactic sugar for a const pointer.
>>
> I guess you meant 'unnullable pointer' rather that 'const pointer'.

No, I meant what I said.

>> [...] The underlying pointer (or equivalent) could be invalid, if the 
>> object
>> it originally referred to having ended it's lifetime, but it can't be
>> null.
> This is possible with C++ references, as well, so if your point is to
prefer 
> C++ references to unnullable poitners, then this argument does not
count.

I was describing C++ references, so of course what I describe is 
possible with C++ references.

>> However, the rules you've chosen for your unnullable pointers are too
>> lax, and make it possible for it to be nulled.
> I do not see any problem with the possibility to make an unnullable
pointer 
> null. If you do, please let me know what it is. After all, if we can
modify 
> a const object, then why not make an unnullable pointer null, as well?

I'd say that the only thing that could make your concept useful would be 
  the assurance that it cannot be null. My point is that without such a 
guarantee, I don't see that it has any great usefulness.
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