handler_ptr

A smart pointer container with associated completion handler.

Synopsis

Defined in header <boost/beast/core/handler_ptr.hpp>

template<
    class T,
    class Handler>
class handler_ptr

Types

Name	Description
element_type	The type of element stored.
handler_type	The type of handler stored.

Member Functions

Name	Description
get	Return a pointer to the owned object.
handler	Return a reference to the handler.
handler_ptr	Default constructor (deleted). Move constructor. Copy constructor (deleted). Constructor.
has_value	Return true if *this owns an object.
invoke	Invoke the handler in the owned object.
operator*	Return a reference to the owned object.
operator->	Return a pointer to the owned object.
operator=	Copy assignment (deleted). Move assignment (deleted).
release_handler	Return ownership of the handler.
~handler_ptr	Destructor.

This is a smart pointer that retains unique ownership of an object through a pointer. Memory is managed using the allocator associated with a completion handler stored in the object. The managed object is destroyed and its memory deallocated when one of the following occurs:

The function handler_ptr::invoke is called.
The function handler_ptr::release_handler is called.
The container is destroyed.

Objects of this type are used in the implementation of composed operations with states that are expensive or impossible to move. This container manages that non-trivial state on behalf of the composed operation.

Thread Safety

Distinct objects: Safe.

Shared objects: Unsafe.

Template Parameters

Type	Description
`T`	The type of the owned object. Must be noexcept destructible.
`Handler`	The type of the completion handler.

Convenience header <boost/beast/core.hpp>