Re: std::istreambuf_iterator

From:
 James Kanze <james.kanze@gmail.com>
Newsgroups:
comp.lang.c++
Date:
Sat, 11 Aug 2007 04:53:23 -0700
Message-ID:
<1186833203.200157.239210@k79g2000hse.googlegroups.com>
On Aug 9, 1:57 pm, ahmadcorp <manz...@gmail.com> wrote:

This should be a simple problem, but I can't seem to figure it out.
Maybe someone can help?


It's a very simple problem, once you've seen it. On the other
hand, I don't know of anyone who hasn't hit it once or twice.

I have a file containing data each line has about 6 entries (numbers)
space delimited and each line has a new line character at the end of
the line. I'd like to read the file in one pass, so I am trying to use
std::istreambuf_iterator as follows (where inputFile is an ifstream):

std::vector<std::string>
data( std::istreambuf_iterator<std::string>(inputFile) ,
std::istreambuf_iterator<std::string>())


Attention: here, you are not defining a variable, but declaring
a function. (Isn't C++ declaration syntax horrible.) You need
to do something so that at least one of the "arguments" can't be
interpreted as a parameter declaration; an extra pair of
parentheses will do the trick:

    std::vector< std::string >
                        data(
            (std::istreambuf_iterator< std::string >( inputFile )),
            (std::istreambuf_iterator< std::string >()) ) ;

(Formally, it's sufficient to add the parentheses to just one of
the arguments, but I like orthogonality.)

--
James Kanze (GABI Software) email:james.ka...@gmail.com
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