Re: If string::c_str() doesn't invalidate iterators ...

From	"Alf P. Steinbach" <alf.p.steinbach@gmail.com>
Newsgroups	comp.lang.c++
Subject	Re: If string::c_str() doesn't invalidate iterators ...
Date	2021-06-24 17:37 +0200
Organization	A noiseless patient Spider
Message-ID	<sb28r5$4m4$1@dont-email.me> (permalink)
References	<sb2646$6um$1@gioia.aioe.org> <d47382b2-2b6f-40c1-bb3c-d89850da882an@googlegroups.com>

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On 24 Jun 2021 17:27, Öö Tiib wrote:
> On Thursday, 24 June 2021 at 17:51:03 UTC+3, Kli-Kla-Klawitter wrote:
>> If string::c_str() doesn't invalidate iterators, I could access
>> str[str.length()] safely myself even it's outside the bounds
>> because the storage for the zero-termination must be pre-allocated
>> to terminate the string in-place. Cooooooooooooooool!
> 
> There are no such strange logic needed. The str[str.length()] is
> required to return reference to null character after last character
> of string. Modifying that null character using the reference is
> undefined behavior.

KKK has probably read some C++03 discussion.

In C++03 the terminating zero in the buffer was only guaranteed via the 
`const` accessors.

The guarantees were revamped for C++11 allegedly for thread safety 
(which I regard as a whole load of bollocks), but incidentally so that a 
design level error in the C++03 COW support was removed -- with that 
bathwater also containing the baby COW, but hey, no pain no gain.

- Alf

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Thread

If string::c_str() doesn't invalidate iterators ... Kli-Kla-Klawitter <kliklaklawitter69@gmail.com> - 2021-06-24 16:50 +0200
  Re: If string::c_str() doesn't invalidate iterators ... Öö Tiib <ootiib@hot.ee> - 2021-06-24 08:27 -0700
    Re: If string::c_str() doesn't invalidate iterators ... "Alf P. Steinbach" <alf.p.steinbach@gmail.com> - 2021-06-24 17:37 +0200

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