Why Strings as Classes? [C++ iterator]

[Fawzi Mohamed]

On 2008-08-28 13:06:59 +0200, Michel Fortin <michel.fortin at michelf.com> said:

> On 2008-08-28 05:47:22 -0400, Fawzi Mohamed <fmohamed at mac.com> said:
> 
>> An iterator should be like a generator, have a method next, and one 
>> at_end or something similar packaged (and maybe prev() and at_start() 
>> if it can also go back) in a single struct, furthermore it should work 
>> seamlessly with a kind of for_each(x;iterator) construct.
> 
> I perfectly agree with this. This is why I prefer much Objective-C's 
> NSEnumerator over C++ iterators: they're much simpler to use.
> 
> Some time ago, Walter asked if he could change D arrays to have 
> internally an end pointer instead of a length value. He said it was to 
> allow arrays, or slices, to be used as iterator efficiently. I hope he 
> hasn't given up on that idea since slices are much easier to understand 
> and use than C++-style iterators.

I agree

>> Instead C++ choose to have begin & end iterators, simply because with 
>> that construct it is trivial for the compiler to optimize it for 
>> arrays, and you can use pointers as iterators without a 
>> cast/constructor.
> 
> I would add that if you are using many iterators for the same array 
> (vector) in a given algorithm or in function parameters, having only 
> one "end" pointer save some space.

ok given, but I would say that one almost never takes advantage of 
this, and even then the real advantage is probably small.