Class template visitor_ptr_t

Boost C++ Libraries

Class template visitor_ptr_t

boost::visitor_ptr_t — Adapts a function pointer for use as a static visitor.

Synopsis

// In header: <boost/variant/visitor_ptr.hpp>

template<typename T, typename R> 
class visitor_ptr_t : public static_visitor<R> {
public:
  // construct/copy/destruct
  explicit visitor_ptr_t(R (*)(T));

  // static visitor interfaces
  R operator()(unspecified-forwarding-type);
  template<typename U> void operator()(const U&);
};

Description

Adapts the function given at construction for use as a static visitor of type T with result type R.

`visitor_ptr_t` public construct/copy/destruct

```
explicit visitor_ptr_t(R (*)(T));
```
Effects:
Constructs the visitor with the given function.

`visitor_ptr_t` static visitor interfaces

R operator()(unspecified-forwarding-type operand);
template<typename U> void operator()(const U&);

Effects:	If passed a value or reference of type `T`, it invokes the function given at construction, appropriately forwarding `operand`.
Returns:	Returns the result of the function invocation.
Throws:	The overload taking a value or reference of type `T` throws if the invoked function throws. The overload taking all other values always throws `bad_visit`.