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// (C) Copyright Jeremy Siek 2000. Permission to copy, use, modify, sell and
// distribute this software is granted provided this copyright notice appears
// in all copies. This software is provided "as is" without express or implied
// warranty, and with no claim as to its suitability for any purpose.
#include <boost/config.hpp>
#include <list>
#include <iostream>
#include <iterator>
#include <algorithm>
#include <string>
#include <boost/iterator_adaptors.hpp>
struct personnel_record {
personnel_record(std::string n, int id) : m_name(n), m_ID(id) { }
std::string m_name;
int m_ID;
};
struct select_name {
typedef personnel_record argument_type;
typedef std::string result_type;
const std::string& operator()(const personnel_record& r) const {
return r.m_name;
}
std::string& operator()(personnel_record& r) const {
return r.m_name;
}
};
struct select_ID {
typedef personnel_record argument_type;
typedef int result_type;
const int& operator()(const personnel_record& r) const {
return r.m_ID;
}
int& operator()(personnel_record& r) const {
return r.m_ID;
}
};
int main(int, char*[])
{
std::list<personnel_record> personnel_list;
personnel_list.push_back(personnel_record("Barney", 13423));
personnel_list.push_back(personnel_record("Fred", 12343));
personnel_list.push_back(personnel_record("Wilma", 62454));
personnel_list.push_back(personnel_record("Betty", 20490));
// Example of using projection_iterator_generator
// to print out the names in the personnel list.
boost::projection_iterator_generator<select_name,
std::list<personnel_record>::iterator>::type
personnel_first(personnel_list.begin()),
personnel_last(personnel_list.end());
std::copy(personnel_first, personnel_last,
std::ostream_iterator<std::string>(std::cout, "\n"));
std::cout << std::endl;
// Example of using projection_iterator_pair_generator
// to assign new ID numbers to the personnel.
typedef boost::projection_iterator_pair_generator<select_ID,
std::list<personnel_record>::iterator,
std::list<personnel_record>::const_iterator> PairGen;
PairGen::iterator ID_first(personnel_list.begin()),
ID_last(personnel_list.end());
int new_id = 0;
while (ID_first != ID_last) {
*ID_first = new_id++;
++ID_first;
}
PairGen::const_iterator const_ID_first(personnel_list.begin()),
const_ID_last(personnel_list.end());
std::copy(const_ID_first, const_ID_last,
std::ostream_iterator<int>(std::cout, " "));
std::cout << std::endl;
std::cout << std::endl;
// Example of using make_const_projection_iterator()
// to print out the names in the personnel list again.
std::copy
(boost::make_const_projection_iterator<select_name>(personnel_list.begin()),
boost::make_const_projection_iterator<select_name>(personnel_list.end()),
std::ostream_iterator<std::string>(std::cout, "\n"));
return 0;
}
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