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Get examples working, mostly. Some interface expansion for a few of

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the adaptors, allowing default construction of UnaryFunction and
Predicate arguments when they are class types.


[SVN r19081]
This commit is contained in:
Dave Abrahams
2003-07-12 04:15:13 +00:00
parent c4b7aaf281
commit 074007ab8c
14 changed files with 135 additions and 1108 deletions
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49
projection_iterator_example.cpp
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@@ -9,7 +9,7 @@
#include <iterator>
#include <algorithm>
#include <string>
#include <boost/iterator_adaptors.hpp>
#include <boost/iterator/transform_iterator.hpp>
struct personnel_record {
personnel_record(std::string n, int id) : m_name(n), m_ID(id) { }
@@ -19,7 +19,7 @@ struct personnel_record {
struct select_name {
typedef personnel_record argument_type;
typedef std::string result_type;
typedef std::string const& result_type;
const std::string& operator()(const personnel_record& r) const {
return r.m_name;
}
@@ -30,7 +30,7 @@ struct select_name {
struct select_ID {
typedef personnel_record argument_type;
typedef int result_type;
typedef int& result_type;
const int& operator()(const personnel_record& r) const {
return r.m_ID;
}
@@ -48,11 +48,16 @@ int main(int, char*[])
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.
// Example of using transform_iterator to print out the names in the
// personnel list using a projection.
boost::projection_iterator_generator<select_name,
std::list<personnel_record>::iterator>::type
boost::transform_iterator<
select_name
, std::list<personnel_record>::iterator
#ifdef BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION
, std::string
#endif
>
personnel_first(personnel_list.begin()),
personnel_last(personnel_list.end());
@@ -60,14 +65,12 @@ int main(int, char*[])
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.
// Example of using transform_iterator with const_iterators 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()),
boost::transform_iterator<
select_ID, std::list<personnel_record>::iterator
> ID_first(personnel_list.begin()),
ID_last(personnel_list.end());
int new_id = 0;
@@ -76,21 +79,25 @@ int main(int, char*[])
++ID_first;
}
PairGen::const_iterator const_ID_first(personnel_list.begin()),
boost::transform_iterator<
select_ID, std::list<personnel_record>::const_iterator, int const&
>
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;
#ifndef BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION
// Example of using make_const_projection_iterator()
// to print out the names in the personnel list again.
std::copy(
boost::make_transform_iterator<select_name>(personnel_list.begin())
, boost::make_transform_iterator<select_name>(personnel_list.end())
, std::ostream_iterator<std::string>(std::cout, "\n"));
#endif
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;
}