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Re: stl copy and istream_iterator and operator >>

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On 09/19/11 09:27 AM, persres@googlemail.com wrote:
> Hi,
>      I have the following code -
>
> string str("12 3213 asdf 21");
> vector<int>  v;
>
> copy(istream_iterator<int>(istringstream(str)) ,
> istream_iterator<int>(),  back_inserter(v) );

This shouldn't compile. You can't create an istream_iterator from a 
temporary.

> I expected copy to throw because the operator>>  would have failed due
> to the 'asdf' string present.

Which operator >>?

> However, it doesn't throw.  Do you know why,

Because the code doesn't do what you think it does (assuming you get it 
to compile).  Have a look at the vector contents.

> How can i get it to throw or return an errror.

You can provide your own input iterator type.

-- 
Ian Collins

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stl copy and  istream_iterator and operator >> "persres@googlemail.com" <persres@gmail.com> - 2011-09-18 14:27 -0700
  Re: stl copy and  istream_iterator and operator >> Ian Collins <ian-news@hotmail.com> - 2011-09-19 09:47 +1200
    Re: stl copy and istream_iterator and operator >> "persres@googlemail.com" <persres@gmail.com> - 2011-09-18 14:53 -0700
      Re: stl copy and istream_iterator and operator >> Ian Collins <ian-news@hotmail.com> - 2011-09-19 10:00 +1200
        Re: stl copy and istream_iterator and operator >> "persres@googlemail.com" <persres@gmail.com> - 2011-09-18 15:11 -0700
          Re: stl copy and istream_iterator and operator >> red floyd <no.spam.here@its.invalid> - 2011-09-18 15:23 -0700
          Re: stl copy and istream_iterator and operator >> Ian Collins <ian-news@hotmail.com> - 2011-09-19 10:23 +1200
            Re: stl copy and istream_iterator and operator >> James Kanze <james.kanze@gmail.com> - 2011-09-19 15:19 -0700
    Re: stl copy and  istream_iterator and operator >> Ian Collins <ian-news@hotmail.com> - 2011-09-19 10:11 +1200

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