deferred

deferred_t

Class used to specify that an asynchronous operation should return a function object to lazily launch the operation.

class deferred_t

Types

Name	Description
as_default_on_t	Type alias to adapt an I/O object to use deferred_t as its default completion token type.
executor_with_default	Adapts an executor to add the deferred_t completion token as the default.

Member Functions

Name	Description
as_default_on [static]	Function helper to adapt an I/O object to use deferred_t as its default completion token type.
deferred_t [constructor]	Default constructor.
operator()	Creates a new deferred from a function. — Passes through anything that is already deferred.
values [static]	Returns a deferred operation that returns the provided values.
when [static]	Creates a conditional object for branching deferred operations.

The deferred_t class is used to indicate that an asynchronous operation should return a function object which is itself an initiation function. A deferred_t object may be passed as a completion token to an asynchronous operation, typically as the default completion token:

auto my_deferred_op = my_socket.async_read_some(my_buffer);

or by explicitly passing the special value boost::asio::deferred:

auto my_deferred_op
 = my_socket.async_read_some(my_buffer,
     boost::asio::deferred);

The initiating function (async_read_some in the above example) returns a function object that will lazily initiate the operation.

Requirements

Header: boost/asio/deferred.hpp

Convenience header: boost/asio.hpp

Boost C++ Libraries

deferred_t

Types

Member Functions

Requirements