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