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Class template visitor_ptr_t

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


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

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


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

visitor_ptr_t construct/copy/destruct

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

visitor_ptr_t static visitor interfaces

  1. 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.
Copyright 2002, 2003 Eric Friedman, Itay Maman