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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 <iostream>
#include <iomanip>
#include <vector>
#include <string>
#include <utility>
#include <boost/coroutine2/all.hpp>
struct FinalEOL{
~FinalEOL(){
std::cout << std::endl;
}
};
int main(int argc,char* argv[]){
using std::begin;
using std::end;
std::vector<std::string> words{
"peas", "porridge", "hot", "peas",
"porridge", "cold", "peas", "porridge",
"in", "the", "pot", "nine",
"days", "old" };
int num=5,width=15;
boost::coroutines2::coroutine<std::string>::push_type writer(
[&](boost::coroutines2::coroutine<std::string>::pull_type& in){
// 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;
}
});
std::copy(begin(words),end(words),begin(writer));
std::cout << "\nDone";
return EXIT_SUCCESS;
}
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