Class function_base

boost::function_base — The common base class for all Boost.Function objects. Objects of type function_base may not be created directly.

Synopsis

class function_base {
public:

  // capacity
  bool empty() const;

  // target access
  template<typename Functor> Functor* target();
  template<typename Functor> const Functor* target() const;
  template<typename Functor> bool contains(const Functor&) const;
  const std::type_info& target_type() const;
};

Description

function_base capacity

```
bool empty() const;
```
Returns:
false if this has a target, and true otherwise.

Throws: Will not throw.

function_base target access

```
template<typename Functor> Functor* target();
template<typename Functor> const Functor* target() const;
```
Returns: If this stores a target of type Functor, returns the address of the target. Otherwise, returns the NULL pointer.

Throws: Will not throw.
```
template<typename Functor> bool contains(const Functor& f) const;
```
Returns: true if this->target<Functor>() is non-NULL and function_equal(*(this->target<Functor>()), f)
```
const std::type_info& target_type() const;
```
Returns: typeid of the target function object, or typeid(void) if this->empty().

Throws: Will not throw.

Returns:	false if this has a target, and true otherwise.
Throws:	Will not throw.

Returns:	If this stores a target of type Functor, returns the address of the target. Otherwise, returns the NULL pointer.
Throws:	Will not throw.

Returns:	typeid of the target function object, or typeid(void) if this->empty().
Throws:	Will not throw.