graphlab::request_future< T > Struct Template Reference

#include <graphlab/rpc/request_future.hpp>

List of all members.

Public Types
typedef dc_impl::function_ret_type< T > ::type	result_type

Public Member Functions
	request_future ()
	default constructor
	request_future (const T &val)
	request_future (const request_future< T > &val)
	copy constructor
request_future &	operator= (const request_future< T > &val)
	operator=
void	wait ()
	explicit call to wait(). Will wait only if the future has no value yet
bool	is_ready ()
result_type &	operator() ()

Public Attributes
std::auto_ptr < dc_impl::reply_ret_type >	reply
result_type	result
bool	hasval

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Detailed Description

template<typename T>
struct graphlab::request_future< T >

The result of a future_remote_request call. This class represents the outcome of a remote request sent to another machine via the future_remote_request_call. The future_remote_request call returns immediately with this object. Only when operator() is called on this object, then it waits for a result from the remote machine.

example:

     // this function returns immediately
     graphlab::request_future<int> res = 
       rmi.future_remote_request(SOME_OTHER_MACHINE, 
                                 function_which_returns_an_integer, ...);
    
     ... we can do other stuff ... 
     // read the result, or wait for the result if it is not done yet.
     int actual_result = res();

The future object holds a copy of the result of the request, and the operator() call returns a reference to this result (once it is available).

Definition at line 36 of file request_future.hpp.

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Constructor & Destructor Documentation

template<typename T>

graphlab::request_future< T >::request_future ( const T &  val )

inline

We can assign return values directly to the future in the case where no remote calls are necessary. Thus allowing the following to be written easily:

     request_future<int> a_function(int arg) {
       if (arg == 0) return rmi.future_remote_request(... somewhere else ...) ;
       else return 10;
     }

Definition at line 57 of file request_future.hpp.

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Member Function Documentation

template<typename T>

result_type& graphlab::request_future< T >::operator() ( )

inline

Waits for the request if it has not yet been received. Otherwise, returns a reference to the received value.

Definition at line 96 of file request_future.hpp.

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The documentation for this struct was generated from the following file:

• graphlab/rpc/request_future.hpp