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foreachnotification(+BaseName, -Message, +Params, +ReceivePort, -Status, +Goals)

A control construct to iterate over received notifications
BaseName
an atom used as the basename for the generated auxiliary predicate
Message
a variable
Params
a list of global variables in the iteration body (as in do/2)
ReceivePort
a receiver structure as created by open_receiver
Status
a variable, will be bound to 'open' or 'closed'
Goals
the goals that will be called for each iteration

Description

This is a control construct iterating over the currently available messages on the given receive port. The purpose is to process the received messages one by one without the need to create an auxiliary list of received messages. The iteration terminates when there are (currently) no more message on the receive port.

When the iteration terminates, the Status argument indicates whether the associated sender is still open ('open') or has been closed ('closed'). If closed, no more messages will arrive on this receive port in the future.

Modules

This predicate is sensitive to its module context (tool predicate, see @/2).

Examples

	process_all_messages(ReceivePort, Log) :-
	    foreachnotification(sample, Message, [Log], ReceivePort, Status, (
		writeln(Log, received(Message)),
		do_something(Message)
	    )),
	    ( Status = closed ->
		writeln(Log, end_of_messages)
	    ;
		writeln(Log, more_coming)
	    ).

See Also

receive_notifications / 3