/Src/Dependencies/Boost/libs/iterator/example/node_iterator3.hpp

 1// Copyright David Abrahams 2004. Use, modification and distribution is
 2// subject to the Boost Software License, Version 1.0. (See accompanying
 3// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
 4#ifndef NODE_ITERATOR3_DWA2004110_HPP
 5# define NODE_ITERATOR3_DWA2004110_HPP
 6
 7# include "node.hpp"
 8# include <boost/iterator/iterator_adaptor.hpp>
 9
10# ifndef BOOST_NO_SFINAE
11#  include <boost/type_traits/is_convertible.hpp>
12#  include <boost/utility/enable_if.hpp>
13# endif
14
15template <class Value>
16class node_iter
17  : public boost::iterator_adaptor<
18        node_iter<Value>                // Derived
19      , Value*                          // Base
20      , boost::use_default              // Value
21      , boost::forward_traversal_tag    // CategoryOrTraversal
22    >
23{
24 private:
25    struct enabler {};  // a private type avoids misuse
26
27    typedef boost::iterator_adaptor<
28        node_iter<Value>, Value*, boost::use_default, boost::forward_traversal_tag
29    > super_t;
30    
31 public:
32    node_iter()
33      : super_t(0) {}
34
35    explicit node_iter(Value* p)
36      : super_t(p) {}
37
38    template <class OtherValue>
39    node_iter(
40        node_iter<OtherValue> const& other
41# ifndef BOOST_NO_SFINAE
42      , typename boost::enable_if<
43            boost::is_convertible<OtherValue*,Value*>
44          , enabler
45        >::type = enabler()
46# endif 
47    )
48      : super_t(other.base()) {}
49
50# if !BOOST_WORKAROUND(__GNUC__, == 2)
51 private: // GCC2 can't grant friendship to template member functions    
52    friend class boost::iterator_core_access;
53# endif     
54    void increment() { this->base_reference() = this->base()->next(); }
55};
56
57typedef node_iter<node_base> node_iterator;
58typedef node_iter<node_base const> node_const_iterator;
59
60#endif // NODE_ITERATOR3_DWA2004110_HPP