Boost C++ Libraries of the most highly regarded and expertly designed C++ library projects in the world. Herb Sutter and Andrei Alexandrescu, C++ Coding Standards

This is the documentation for a snapshot of the develop branch, built from commit 3475a457cf.



    Copyright (c) 2003-2007 Fernando Luis Cacciola Carballal
    Copyright (c) 2015 Andrzej Krzemienski

    Distributed under the Boost Software License, Version 1.0.
    (See accompanying file LICENSE_1_0.txt or copy at

[section Header <boost/optional/optional_fwd.hpp>]

[section Synopsis]
namespace boost {

template <class T> class optional ;

template <class T> void swap ( optional<T>& , optional<T>& );

template <class T> struct optional_swap_should_use_default_constructor ;
} // namespace boost

This header only contains declarations.