| // Boost.Signals library |
| |
| // Copyright Douglas Gregor 2001-2004. 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_SIGNALS_SLOT_CALL_ITERATOR |
| #define BOOST_SIGNALS_SLOT_CALL_ITERATOR |
| |
| #include <memory> |
| #include <boost/iterator/iterator_facade.hpp> |
| #include <boost/smart_ptr.hpp> |
| #include <boost/signals/detail/config.hpp> |
| #include <boost/signals/connection.hpp> |
| #include <boost/optional.hpp> |
| |
| #ifdef BOOST_HAS_ABI_HEADERS |
| # include BOOST_ABI_PREFIX |
| #endif |
| |
| namespace boost { |
| namespace BOOST_SIGNALS_NAMESPACE { |
| namespace detail { |
| |
| // Generates a slot call iterator. Essentially, this is an iterator that: |
| // - skips over disconnected slots in the underlying list |
| // - calls the connected slots when dereferenced |
| // - caches the result of calling the slots |
| template<typename Function, typename Iterator> |
| class slot_call_iterator |
| : public iterator_facade<slot_call_iterator<Function, Iterator>, |
| typename Function::result_type, |
| single_pass_traversal_tag, |
| typename Function::result_type const&> |
| { |
| typedef iterator_facade<slot_call_iterator<Function, Iterator>, |
| typename Function::result_type, |
| single_pass_traversal_tag, |
| typename Function::result_type const&> |
| inherited; |
| |
| typedef typename Function::result_type result_type; |
| |
| friend class iterator_core_access; |
| |
| public: |
| slot_call_iterator(Iterator iter_in, Iterator end_in, Function f, |
| optional<result_type> &c) |
| : iter(iter_in), end(end_in), f(f), cache(&c) |
| { |
| iter = std::find_if(iter, end, is_callable()); |
| } |
| |
| typename inherited::reference |
| dereference() const |
| { |
| if (!cache->is_initialized()) { |
| cache->reset(f(*iter)); |
| } |
| |
| return cache->get(); |
| } |
| |
| void increment() |
| { |
| iter = std::find_if(++iter, end, is_callable()); |
| cache->reset(); |
| } |
| |
| bool equal(const slot_call_iterator& other) const |
| { |
| iter = std::find_if(iter, end, is_callable()); |
| other.iter = std::find_if(other.iter, other.end, |
| is_callable()); |
| return iter == other.iter; |
| } |
| |
| private: |
| mutable Iterator iter; |
| Iterator end; |
| Function f; |
| optional<result_type>* cache; |
| }; |
| } // end namespace detail |
| } // end namespace BOOST_SIGNALS_NAMESPACE |
| } // end namespace boost |
| |
| #ifdef BOOST_HAS_ABI_HEADERS |
| # include BOOST_ABI_SUFFIX |
| #endif |
| |
| #endif // BOOST_SIGNALS_SLOT_CALL_ITERATOR |