///////////////////////////////////////////////////////////////////////////// | |
// | |
// (C) Copyright Ion Gaztanaga 2007-2009 | |
// | |
// 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) | |
// | |
// See http://www.boost.org/libs/intrusive for documentation. | |
// | |
///////////////////////////////////////////////////////////////////////////// | |
#ifndef BOOST_INTRUSIVE_DETAIL_TRANSFORM_ITERATOR_HPP | |
#define BOOST_INTRUSIVE_DETAIL_TRANSFORM_ITERATOR_HPP | |
#include <boost/intrusive/detail/config_begin.hpp> | |
#include <iterator> | |
#include <boost/intrusive/detail/mpl.hpp> | |
namespace boost { | |
namespace intrusive { | |
namespace detail { | |
template <class PseudoReference> | |
struct operator_arrow_proxy | |
{ | |
operator_arrow_proxy(const PseudoReference &px) | |
: m_value(px) | |
{} | |
PseudoReference* operator->() const { return &m_value; } | |
// This function is needed for MWCW and BCC, which won't call operator-> | |
// again automatically per 13.3.1.2 para 8 | |
// operator T*() const { return &m_value; } | |
mutable PseudoReference m_value; | |
}; | |
template <class T> | |
struct operator_arrow_proxy<T&> | |
{ | |
operator_arrow_proxy(T &px) | |
: m_value(px) | |
{} | |
T* operator->() const { return &m_value; } | |
// This function is needed for MWCW and BCC, which won't call operator-> | |
// again automatically per 13.3.1.2 para 8 | |
// operator T*() const { return &m_value; } | |
T &m_value; | |
}; | |
template <class Iterator, class UnaryFunction> | |
class transform_iterator | |
: public std::iterator | |
< typename Iterator::iterator_category | |
, typename detail::remove_reference<typename UnaryFunction::result_type>::type | |
, typename Iterator::difference_type | |
, operator_arrow_proxy<typename UnaryFunction::result_type> | |
, typename UnaryFunction::result_type> | |
{ | |
public: | |
explicit transform_iterator(const Iterator &it, const UnaryFunction &f = UnaryFunction()) | |
: members_(it, f) | |
{} | |
explicit transform_iterator() | |
: members_() | |
{} | |
Iterator get_it() const | |
{ return members_.m_it; } | |
//Constructors | |
transform_iterator& operator++() | |
{ increment(); return *this; } | |
transform_iterator operator++(int) | |
{ | |
transform_iterator result (*this); | |
increment(); | |
return result; | |
} | |
friend bool operator== (const transform_iterator& i, const transform_iterator& i2) | |
{ return i.equal(i2); } | |
friend bool operator!= (const transform_iterator& i, const transform_iterator& i2) | |
{ return !(i == i2); } | |
/* | |
friend bool operator> (const transform_iterator& i, const transform_iterator& i2) | |
{ return i2 < i; } | |
friend bool operator<= (const transform_iterator& i, const transform_iterator& i2) | |
{ return !(i > i2); } | |
friend bool operator>= (const transform_iterator& i, const transform_iterator& i2) | |
{ return !(i < i2); } | |
*/ | |
friend typename Iterator::difference_type operator- (const transform_iterator& i, const transform_iterator& i2) | |
{ return i2.distance_to(i); } | |
//Arithmetic | |
transform_iterator& operator+=(typename Iterator::difference_type off) | |
{ this->advance(off); return *this; } | |
transform_iterator operator+(typename Iterator::difference_type off) const | |
{ | |
transform_iterator other(*this); | |
other.advance(off); | |
return other; | |
} | |
friend transform_iterator operator+(typename Iterator::difference_type off, const transform_iterator& right) | |
{ return right + off; } | |
transform_iterator& operator-=(typename Iterator::difference_type off) | |
{ this->advance(-off); return *this; } | |
transform_iterator operator-(typename Iterator::difference_type off) const | |
{ return *this + (-off); } | |
typename UnaryFunction::result_type operator*() const | |
{ return dereference(); } | |
operator_arrow_proxy<typename UnaryFunction::result_type> | |
operator->() const | |
{ return operator_arrow_proxy<typename UnaryFunction::result_type>(dereference()); } | |
private: | |
struct members | |
: UnaryFunction | |
{ | |
members(const Iterator &it, const UnaryFunction &f) | |
: UnaryFunction(f), m_it(it) | |
{} | |
members() | |
{} | |
Iterator m_it; | |
} members_; | |
void increment() | |
{ ++members_.m_it; } | |
void decrement() | |
{ --members_.m_it; } | |
bool equal(const transform_iterator &other) const | |
{ return members_.m_it == other.members_.m_it; } | |
bool less(const transform_iterator &other) const | |
{ return other.members_.m_it < members_.m_it; } | |
typename UnaryFunction::result_type dereference() const | |
{ return members_(*members_.m_it); } | |
void advance(typename Iterator::difference_type n) | |
{ std::advance(members_.m_it, n); } | |
typename Iterator::difference_type distance_to(const transform_iterator &other)const | |
{ return std::distance(other.members_.m_it, members_.m_it); } | |
}; | |
} //namespace detail | |
} //namespace intrusive | |
} //namespace boost | |
#include <boost/intrusive/detail/config_end.hpp> | |
#endif //BOOST_INTRUSIVE_DETAIL_TRANSFORM_ITERATOR_HPP |