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Diffstat (limited to '3rdParty/Boost/src/boost/signals2/last_value.hpp')
-rw-r--r-- | 3rdParty/Boost/src/boost/signals2/last_value.hpp | 78 |
1 files changed, 78 insertions, 0 deletions
diff --git a/3rdParty/Boost/src/boost/signals2/last_value.hpp b/3rdParty/Boost/src/boost/signals2/last_value.hpp new file mode 100644 index 0000000..51cc541 --- /dev/null +++ b/3rdParty/Boost/src/boost/signals2/last_value.hpp @@ -0,0 +1,78 @@ +// last_value function object (documented as part of Boost.Signals) + +// Copyright Frank Mori Hess 2007. +// Copyright Douglas Gregor 2001-2003. Use, modification and +// distribution is subject to 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) + +// For more information, see http://www.boost.org + +#ifndef BOOST_SIGNALS2_LAST_VALUE_HPP +#define BOOST_SIGNALS2_LAST_VALUE_HPP + +#include <boost/optional.hpp> +#include <boost/signals2/expired_slot.hpp> +#include <boost/throw_exception.hpp> +#include <stdexcept> + +namespace boost { + namespace signals2 { + + // no_slots_error is thrown when we are unable to generate a return value + // due to no slots being connected to the signal. + class no_slots_error: public std::exception + { + public: + virtual const char* what() const throw() {return "boost::signals2::no_slots_error";} + }; + + template<typename T> + class last_value { + public: + typedef T result_type; + + template<typename InputIterator> + T operator()(InputIterator first, InputIterator last) const + { + if(first == last) + { + boost::throw_exception(no_slots_error()); + } + optional<T> value; + while (first != last) + { + try + { + value = *first; + } + catch(const expired_slot &) {} + ++first; + } + if(value) return value.get(); + boost::throw_exception(no_slots_error()); + } + }; + + template<> + class last_value<void> { + public: + typedef void result_type; + template<typename InputIterator> + result_type operator()(InputIterator first, InputIterator last) const + { + while (first != last) + { + try + { + *first; + } + catch(const expired_slot &) {} + ++first; + } + return; + } + }; + } // namespace signals2 +} // namespace boost +#endif // BOOST_SIGNALS2_LAST_VALUE_HPP |