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That's the question: should the standard explicitly *require* that
`basic_string`, `vector`, and `array` iterators are pointers? Along with
any similar types we get (there's been some talk about `stack_array` or
whatever).

Let's break down the use cases. That is, why do we want them to be pointers?

1) Performance.

2) The ability to use such iterators in pointer-based interfaces without
having to do `&*` on them.

3) The ability to get pointers back from pointer-based interfaces and use
them easily.

I've always felt that #1 should always be considered a question of the
implementation. I *want* the ability for debug builds to be able to do
range checking for me. I also want those checks to vanish in release builds.

But I think we can achieve #2 and #3 without needing to make them
explicitly pointers. We simply need two changes:

A) Allow these iterators of these types to be *implicitly convertible* to
pointers. That solves #2 neatly.

B) Allow users to convert a pointer to some element into an iterator. That
solves #3 neatly.

B should be a (possibly non-member) function of the *container*. That is,
you shouldn't be able to implicitly construct an iterator from a pointer.
The container ought to verify that the pointer is actually within the range
before doing so. And as a non-member function, it can be specialized/ADL'd
for different types.

Are these good ideas?

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<div dir=3D"ltr">That&#39;s the question: should the standard explicitly <i=
>require</i> that `basic_string`, `vector`, and `array` iterators are point=
ers? Along with any similar types we get (there&#39;s been some talk about =
`stack_array` or whatever).<br><br>Let&#39;s break down the use cases. That=
 is, why do we want them to be pointers?<br><br>1) Performance.<br><br>2) T=
he ability to use such iterators in pointer-based interfaces without having=
 to do `&amp;*` on them.<br><br>3) The ability to get pointers back from po=
inter-based interfaces and use them easily.<br><br>I&#39;ve always felt tha=
t #1 should always be considered a question of the implementation. I <i>wan=
t</i> the ability for debug builds to be able to do range checking for me. =
I also want those checks to vanish in release builds.<br><br>But I think we=
 can achieve #2 and #3 without needing to make them explicitly pointers. We=
 simply need two changes:<br><br>A) Allow these iterators of these types to=
 be <i>implicitly convertible</i> to pointers. That solves #2 neatly.<br><b=
r>B) Allow users to convert a pointer to some element into an iterator. Tha=
t solves #3 neatly.<br><br>B should be a (possibly non-member) function of =
the <i>container</i>. That is, you shouldn&#39;t be able to implicitly cons=
truct an iterator from a pointer. The container ought to verify that the po=
inter is actually within the range before doing so. And as a non-member fun=
ction, it can be specialized/ADL&#39;d for different types.<br><br>Are thes=
e good ideas?<br></div>

<p></p>

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