boost/signals/slot.hpp
// Boost.Signals library
// Copyright Doug 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_SIGNALS_SLOT_HEADER
#define BOOST_SIGNALS_SLOT_HEADER
#include <boost/signals/detail/signals_common.hpp>
#include <boost/signals/connection.hpp>
#include <boost/signals/trackable.hpp>
#include <boost/visit_each.hpp>
#include <cassert>
#ifdef BOOST_HAS_ABI_HEADERS
# include BOOST_ABI_PREFIX
#endif
namespace boost {
namespace BOOST_SIGNALS_NAMESPACE {
namespace detail {
class BOOST_SIGNALS_DECL slot_base {
// We would have to enumerate all of the signalN classes here as
// friends to make this private (as it otherwise should be). We can't
// name all of them because we don't know how many there are.
public:
// Get the set of bound objects
std::vector<const trackable*>& get_bound_objects() const
{ return bound_objects; }
// Determine if this slot is still "active", i.e., all of the bound
// objects still exist
bool is_active() const { return watch_bound_objects.connected(); }
protected:
// Create a connection for this slot
void create_connection();
mutable std::vector<const trackable*> bound_objects;
connection watch_bound_objects;
private:
static void bound_object_destructed(void*, void*) {}
};
} // end namespace detail
// Get the slot so that it can be copied
template<typename F>
reference_wrapper<const F>
get_invocable_slot(const F& f, BOOST_SIGNALS_NAMESPACE::detail::signal_tag)
{ return reference_wrapper<const F>(f); }
template<typename F>
const F&
get_invocable_slot(const F& f, BOOST_SIGNALS_NAMESPACE::detail::reference_tag)
{ return f; }
template<typename F>
const F&
get_invocable_slot(const F& f, BOOST_SIGNALS_NAMESPACE::detail::value_tag)
{ return f; }
// Get the slot so that it can be inspected for trackable objects
template<typename F>
const F&
get_inspectable_slot(const F& f, BOOST_SIGNALS_NAMESPACE::detail::signal_tag)
{ return f; }
template<typename F>
const F&
get_inspectable_slot(const reference_wrapper<F>& f, BOOST_SIGNALS_NAMESPACE::detail::reference_tag)
{ return f.get(); }
template<typename F>
const F&
get_inspectable_slot(const F& f, BOOST_SIGNALS_NAMESPACE::detail::value_tag)
{ return f; }
// Determines the type of the slot - is it a signal, a reference to a
// slot or just a normal slot.
template<typename F>
typename BOOST_SIGNALS_NAMESPACE::detail::get_slot_tag<F>::type
tag_type(const F&)
{
typedef typename BOOST_SIGNALS_NAMESPACE::detail::get_slot_tag<F>::type
the_tag_type;
the_tag_type tag = the_tag_type();
return tag;
}
} // end namespace BOOST_SIGNALS_NAMESPACE
template<typename SlotFunction>
class slot : public BOOST_SIGNALS_NAMESPACE::detail::slot_base {
public:
template<typename F>
slot(const F& f) : slot_function(BOOST_SIGNALS_NAMESPACE::get_invocable_slot(f, BOOST_SIGNALS_NAMESPACE::tag_type(f)))
{
// Visit each of the bound objects and store them for later use
// An exception thrown here will allow the basic_connection to be
// destroyed when this goes out of scope, and no other connections
// have been made.
BOOST_SIGNALS_NAMESPACE::detail::bound_objects_visitor do_bind(bound_objects);
visit_each(do_bind, BOOST_SIGNALS_NAMESPACE::get_inspectable_slot(f, BOOST_SIGNALS_NAMESPACE::tag_type(f)));
create_connection();
}
#ifdef __BORLANDC__
template<typename F>
slot(F* f) : slot_function(f)
{
create_connection();
}
#endif // __BORLANDC__
// We would have to enumerate all of the signalN classes here as friends
// to make this private (as it otherwise should be). We can't name all of
// them because we don't know how many there are.
public:
// Get the slot function to call the actual slot
const SlotFunction& get_slot_function() const { return slot_function; }
private:
slot(); // no default constructor
slot& operator=(const slot&); // no assignment operator
SlotFunction slot_function;
};
} // end namespace boost
#ifdef BOOST_HAS_ABI_HEADERS
# include BOOST_ABI_SUFFIX
#endif
#endif // BOOST_SIGNALS_SLOT_HEADER