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// Copyright Nat Goodspeed 2013.
// Distributed under the Boost Software License, Version 1.0.
// (See accompanying file LICENSE_1_0.txt or copy at
// http://www.boost.org/LICENSE_1_0.txt)
#include <boost/coroutine/all.hpp>
#include <iostream>
#include <iomanip>
#include <vector>
#include <string>
#include <utility>
#include <boost/assign/list_of.hpp>
#include <boost/bind.hpp>
#include <boost/range.hpp>
struct FinalEOL
{
~FinalEOL() { std::cout << std::endl; }
};
void layout(boost::coroutines::asymmetric_coroutine<std::string>::pull_type& in, int num, int width)
{
// Finish the last line when we leave by whatever means
FinalEOL eol;
// Pull values from upstream, lay them out 'num' to a line
for (;;)
{
for (int i = 0; i < num; ++i)
{
// when we exhaust the input, stop
if (! in)
return;
std::cout << std::setw(width) << in.get();
// now that we've handled this item, advance to next
in();
}
// after 'num' items, line break
std::cout << std::endl;
}
}
int main(int argc, char *argv[])
{
std::vector<std::string> words = boost::assign::list_of
("peas")
("porridge")
("hot")
("peas")
("porridge")
("cold")
("peas")
("porridge")
("in")
("the")
("pot")
("nine")
("days")
("old")
;
boost::coroutines::asymmetric_coroutine<std::string>::push_type writer(
boost::bind(layout, _1, 5, 15));
std::copy(boost::begin(words), boost::end(words), boost::begin(writer));
std::cout << "\nDone" << std::endl;
return EXIT_SUCCESS;
}
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