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Re: Putting two colons before std -- is it ever needed?

From Ian Collins <ian-news@hotmail.com>
Newsgroups comp.lang.c++
Subject Re: Putting two colons before std -- is it ever needed?
Date 2019-09-25 20:15 +1200
Message-ID <gv0m18FldqU3@mid.individual.net> (permalink)
References <a23612ee-39c5-4b1b-991a-212689fdbfaf@googlegroups.com>

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On 25/09/2019 20:02, Frederick Gotham wrote:
> 
> Occasionally I see people write code like this:
> 
> #include <string>
> 
> int main()
> {
>      ::std::string str;
> }
> 
> I think you would only ever need to put those two colons before 'std' if you created a class or a namespace called 'std', and of course if you did, then it would have to be inside another namespace (because otherwise you'd have a name clash).
> 
> I tried compiling the following code, and each time it created a 'string' from the C++ standard library.
> 
> So the question I ask is if there is **ever** any situation when it's necessary to put two colons before 'std'?

In theory, maybe. In practice, no never.

-- 
Ian

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Thread

Putting two colons before std -- is it ever needed? Frederick Gotham <cauldwell.thomas@gmail.com> - 2019-09-25 01:02 -0700
  Re: Putting two colons before std -- is it ever needed? Ian Collins <ian-news@hotmail.com> - 2019-09-25 20:15 +1200
  Re: Putting two colons before std -- is it ever needed? David Brown <david.brown@hesbynett.no> - 2019-09-25 12:22 +0200
    Re: Putting two colons before std -- is it ever needed? Frederick Gotham <cauldwell.thomas@gmail.com> - 2019-09-25 03:48 -0700
  Re: Putting two colons before std -- is it ever needed? Bo Persson <bo@bo-persson.se> - 2019-09-25 15:48 +0200
    Re: Putting two colons before std -- is it ever needed? Vir Campestris <vir.campestris@invalid.invalid> - 2019-09-26 21:51 +0100
  Re: Putting two colons before std -- is it ever needed? James Kuyper <jameskuyper@alumni.caltech.edu> - 2019-09-25 10:02 -0400
    Re: Putting two colons before std -- is it ever needed? James Kuyper <jameskuyper@alumni.caltech.edu> - 2019-09-25 10:11 -0400
    Re: Putting two colons before std -- is it ever needed? Frederick Gotham <cauldwell.thomas@gmail.com> - 2019-09-25 07:17 -0700
  Re: Putting two colons before std -- is it ever needed? Stuart Redmann <DerTopper@web.de> - 2019-09-25 19:51 +0200
    Re: Putting two colons before std -- is it ever needed? James Kuyper <jameskuyper@alumni.caltech.edu> - 2019-09-25 15:37 -0400
    Re: Putting two colons before std -- is it ever needed? Frederick Gotham <cauldwell.thomas@gmail.com> - 2019-09-26 00:01 -0700
  Re: Putting two colons before std -- is it ever needed? woodbrian77@gmail.com - 2019-09-27 08:50 -0700
    Re: Putting two colons before std -- is it ever needed? scott@slp53.sl.home (Scott Lurndal) - 2019-09-27 16:25 +0000
      Re: Putting two colons before std -- is it ever needed? woodbrian77@gmail.com - 2019-09-27 11:40 -0700
        Re: Putting two colons before std -- is it ever needed? scott@slp53.sl.home (Scott Lurndal) - 2019-09-27 20:19 +0000

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