Re: C++ Primer ex 9.14

From:
Barry <dhb2000@gmail.com>
Newsgroups:
comp.lang.c++
Date:
Mon, 17 Sep 2007 09:42:37 +0800
Message-ID:
<fckm2d$q6d$1@aioe.org>
James Kanze wrote:

On Sep 16, 1:02 pm, Erik Wikstr?m <Erik-wikst...@telia.com> wrote:
    [...]

It runs fine. Is there any way I can replace what while loop with
std::copy ?


Might be, you would have to use std::istream_iterators and a back insert
iterator to add the elements to the vector, something like (untested):

std::copy(
   std::istream_iterator<std::string>(std::cin),
   std::istream_iterator<std::string>() // The same as end() for a stream
   std::back_insert_iterator<std::vector>(vec)
);


Even simpler would be to use the istream_iterators to initialize
the container. Something like:

    std::vector< std::string > vec(
        (std::istream_iterator< std::string >( std::cin )),

           ^ ^
if it's not for formatting, then it's
not necessary as std::cin is not a type,

        (std::istream_iterator< std::string >()) ) ;

(Note that the outermost parentheses around the arguments are
necessary to prevent the compiler from interpreting the
statement as a function declaration.)


and it's not a function declaration I think. As "TypeA ()" is a function
type who returns "TypeA". So if the compiler wrongly interpret this way,
then it will report that "passing a type is illegal" (I just made this
wording :-) )

it only happens to those with none parameter like the latter one you wrote.

--
Thanks
Barry

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