* The function_base class contains the basic elements needed for the * function1, function2, function3, etc. classes. It is common to all * functions (and as such can be used to tell if we have one of the * functionN objects). */
| 604 | * functionN objects). |
| 605 | */ |
| 606 | class function_base |
| 607 | { |
| 608 | public: |
| 609 | function_base() : vtable(0) { } |
| 610 | |
| 611 | /** Determine if the function is empty (i.e., has no target). */ |
| 612 | bool empty() const { return !vtable; } |
| 613 | |
| 614 | /** Retrieve the type of the stored function object, or type_id<void>() |
| 615 | if this is empty. */ |
| 616 | const boost::core::typeinfo& target_type() const |
| 617 | { |
| 618 | if (!vtable) return BOOST_CORE_TYPEID(void); |
| 619 | |
| 620 | detail::function::function_buffer type; |
| 621 | get_vtable()->manager(functor, type, detail::function::get_functor_type_tag); |
| 622 | return *type.members.type.type; |
| 623 | } |
| 624 | |
| 625 | template<typename Functor> |
| 626 | Functor* target() |
| 627 | { |
| 628 | if (!vtable) return 0; |
| 629 | |
| 630 | detail::function::function_buffer type_result; |
| 631 | type_result.members.type.type = &BOOST_CORE_TYPEID(Functor); |
| 632 | type_result.members.type.const_qualified = is_const<Functor>::value; |
| 633 | type_result.members.type.volatile_qualified = is_volatile<Functor>::value; |
| 634 | get_vtable()->manager(functor, type_result, |
| 635 | detail::function::check_functor_type_tag); |
| 636 | return static_cast<Functor*>(type_result.members.obj_ptr); |
| 637 | } |
| 638 | |
| 639 | template<typename Functor> |
| 640 | const Functor* target() const |
| 641 | { |
| 642 | if (!vtable) return 0; |
| 643 | |
| 644 | detail::function::function_buffer type_result; |
| 645 | type_result.members.type.type = &BOOST_CORE_TYPEID(Functor); |
| 646 | type_result.members.type.const_qualified = true; |
| 647 | type_result.members.type.volatile_qualified = is_volatile<Functor>::value; |
| 648 | get_vtable()->manager(functor, type_result, |
| 649 | detail::function::check_functor_type_tag); |
| 650 | // GCC 2.95.3 gets the CV qualifiers wrong here, so we |
| 651 | // can't do the static_cast that we should do. |
| 652 | return static_cast<const Functor*>(type_result.members.obj_ptr); |
| 653 | } |
| 654 | |
| 655 | template<typename F> |
| 656 | typename boost::enable_if_< !boost::is_function<F>::value, bool >::type |
| 657 | contains(const F& f) const |
| 658 | { |
| 659 | if (const F* fp = this->template target<F>()) |
| 660 | { |
| 661 | return function_equal(*fp, f); |
| 662 | } else { |
| 663 | return false; |