//
// weak_ptr.hpp
//
-// Copyright (c) 2001, 2002 Peter Dimov
+// Copyright (c) 2001, 2002, 2003 Peter Dimov
//
-// 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.
+// 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/smart_ptr/weak_ptr.htm for documentation.
//
-#include <boost/shared_ptr.hpp>
-
-#ifdef BOOST_MSVC // moved here to work around VC++ compiler crash
-# pragma warning(push)
-# pragma warning(disable:4284) // odd return type for operator->
-#endif
-
-namespace boost
-{
-
-template<typename T> class weak_ptr
-{
-private:
-
- // Borland 5.5.1 specific workarounds
- typedef weak_ptr<T> this_type;
-
-public:
-
- typedef T element_type;
-
- weak_ptr(): px(0), pn()
- {
- }
-
-// generated copy constructor, assignment, destructor are fine
-
- template<typename Y>
- weak_ptr(weak_ptr<Y> const & r): px(r.px), pn(r.pn) // never throws
- {
- }
-
- template<typename Y>
- weak_ptr(shared_ptr<Y> const & r): px(r.px), pn(r.pn) // never throws
- {
- }
-
-#if !defined(BOOST_MSVC) || (BOOST_MSVC > 1200)
-
- template<typename Y>
- weak_ptr & operator=(weak_ptr<Y> const & r) // never throws
- {
- px = r.px;
- pn = r.pn;
- return *this;
- }
-
- template<typename Y>
- weak_ptr & operator=(shared_ptr<Y> const & r) // never throws
- {
- px = r.px;
- pn = r.pn;
- return *this;
- }
-
-#endif
-
- void reset()
- {
- this_type().swap(*this);
- }
-
- T * get() const // never throws; deprecated, removal pending, don't use
- {
- return pn.use_count() == 0? 0: px;
- }
-
- long use_count() const // never throws
- {
- return pn.use_count();
- }
-
- bool expired() const // never throws
- {
- return pn.use_count() == 0;
- }
-
- void swap(this_type & other) // never throws
- {
- std::swap(px, other.px);
- pn.swap(other.pn);
- }
-
- bool less(this_type const & rhs) const // implementation detail, never throws
- {
- return pn < rhs.pn;
- }
-
-// Tasteless as this may seem, making all members public allows member templates
-// to work in the absence of member template friends. (Matthew Langston)
-
-#ifndef BOOST_NO_MEMBER_TEMPLATE_FRIENDS
-
-private:
-
- template<typename Y> friend class weak_ptr;
- template<typename Y> friend class shared_ptr;
-
-#endif
-
- T * px; // contained pointer
- detail::weak_count pn; // reference counter
-
-}; // weak_ptr
-
-template<class T, class U> inline bool operator==(weak_ptr<T> const & a, weak_ptr<U> const & b)
-{
- return a.get() == b.get();
-}
-
-template<class T, class U> inline bool operator!=(weak_ptr<T> const & a, weak_ptr<U> const & b)
-{
- return a.get() != b.get();
-}
-
-#if __GNUC__ == 2 && __GNUC_MINOR__ <= 96
-
-// Resolve the ambiguity between our op!= and the one in rel_ops
-
-template<typename T> inline bool operator!=(weak_ptr<T> const & a, weak_ptr<T> const & b)
-{
- return a.get() != b.get();
-}
-
-#endif
-
-template<class T> inline bool operator<(weak_ptr<T> const & a, weak_ptr<T> const & b)
-{
- return a.less(b);
-}
-
-template<class T> void swap(weak_ptr<T> & a, weak_ptr<T> & b)
-{
- a.swap(b);
-}
-
-template<class T> shared_ptr<T> make_shared(weak_ptr<T> const & r) // never throws
-{
- // optimization: avoid throw overhead
- if(r.use_count() == 0)
- {
- return shared_ptr<T>();
- }
-
- try
- {
- return shared_ptr<T>(r);
- }
- catch(use_count_is_zero const &)
- {
- return shared_ptr<T>();
- }
-}
-
-// Note: there is no get_pointer overload for weak_ptr.
-// This is intentional. Even get() will disappear in a
-// future release; these accessors are too error-prone.
-
-} // namespace boost
-
-#ifdef BOOST_MSVC
-# pragma warning(pop)
-#endif
+#include <boost/smart_ptr/weak_ptr.hpp>
#endif // #ifndef BOOST_WEAK_PTR_HPP_INCLUDED