[PATCH] Tiny tweak of the original fix for 8347

[Paolo Carlini]

Gabriel Dos Reis wrote:

>Paolo Carlini <pcarlini@unitus.it> writes:
>
>| +
>| +	size_type __dnew = static_cast<size_type>(distance(__beg, __end));
>
>Please, do fully qualify the above use of distance() with std::.
>
>If you use a standard function *internally*, not mandated by the
>interface then, please don't invoke Koenig lookup.
>
Ah, yes, I have already seen some patches from Phil correcting this kind 
of problems.

I will take the occasion to do it for this instance.

Thanks!

Ciao, Paolo.