input_iterator.cpp

C++的一个好库。。。现在很流行

// Copyright David Abrahams 2002.
// 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/python/module.hpp>
#include <boost/python/def.hpp>
#include <boost/python/class.hpp>
#include <boost/python/iterator.hpp>
#include <boost/iterator/transform_iterator.hpp>
#include <list>

using namespace boost::python;

typedef std::list<int> list_int;

// Prove that we can handle InputIterators which return rvalues.
struct doubler
{
    typedef int result_type;
    int operator()(int x) const { return x * 2; }
};

typedef boost::transform_iterator<doubler, list_int::iterator> doubling_iterator;
typedef std::pair<doubling_iterator,doubling_iterator> list_range2;

list_range2 range2(list_int& x)
{
    return list_range2(
        boost::make_transform_iterator<doubler>(x.begin(), doubler())
      , boost::make_transform_iterator<doubler>(x.end(), doubler()));
}

// We do this in a separate module from iterators_ext (iterators.cpp)
// to work around an MSVC6 linker bug, which causes it to complain
// about a "duplicate comdat" if the input iterator is instantiated in
// the same module with the others.
BOOST_PYTHON_MODULE(input_iterator)
{
    def("range2", &::range2);
    
    class_<list_range2>("list_range2")
        // We can wrap InputIterators which return by-value
        .def("__iter__"
             , range(&list_range2::first, &list_range2::second))
        ;
}

#include "module_tail.cpp"