Message-format Layer Prolog API (Version 1.20)
==============================================

The "message_format" module is for composing and decomposing
messages. It is only recommended if you do not have to
send/receive any message. Otherwise please use the "messaging"
module.

Message Composition & Manipulation
----------------------------------

1.	Contextual-info Composition

	mf_compose_context(	?Version,
				?Conv_id,
				?Origin,
				?Destination,
				-Time_stamp,
				-Context)

	Compose the message contextual-info from given components
	or build a template for receiving messages.

	When composing a message, "Conv_id" should be instantiated.
	The programmer has the freedom to use anything for "Conv_id".
	If "Conv_id" is left uninstantiated, it will be filled in by
	calling "generate_id/1" when the message is sent.

	In composing a message matching template, "Conv_id" can be
	left uninstantiated.

	For most cases, "Time_stamp" should be left uninstantiated.
	It will be filled in when the message is sent.


2.	CCQL Message-core Composition

	mf_compose_ccql_core(	?Performative,
				-Arguments,
				-Core)

	Compose the CCQL message-core from given components
	or build a template for receiving messages.
	"Arguments" is a list in the form:

		[arg1:value1, arg2:value2, ...]

	If the message is used as a receiving template,
	it is suggested to leave "Arguments" uninstantiated.


3.	Message Composition

	mf_compose_message(?Context,?Core,-Message)

	Compose a message from the contextual-info and the message-core.
	"Message" is the message composed.
	"Context" is the contextual-info composed by mf_compose_context/6.
	"Core" is the message-core composed by mf_compose_ccql_core/5.


	mf_compose_message(	?Original,
				?Destination,
				?Performative,
				?Arguments,
				-Message)

	This is a handy way of composing a message from the
	major CCQL components with most information filled in
	by the system.

	"Original" and "Destination" are the original and
	destination names in the contextual part.
	They DO NOT correspond to the sender & reciever argument
	in the CCQL message core, although in most cases they
	should be the same.
	The programmer should set the appropriate sender & receiver
	values in the argument list by "mf_set_argument/2/3".


4.	Message Decomposition

	mf_decompose_message(	?Context,
				?Core,
				+Message)

	Decompose a message into the contextual-info
	& CCQL message-core.


	mf_decompose_message(	?Original,
				?Destination,
				?Performative,
				?Arguments,
				+Message)

	Decompose a message into the corresponding CCQL message
	components. "Arguments" is a list in the form:

		[arg1:value1, arg2:value2, ...]

	As in mf_compose_message/5, "Original" & "Destination" correspond
	to the values in the contextual-info part. To get the sender &
	receiver value in the CCQL message core, use "mf_get_argument/2".


5.	Contextual-info Decomposition

	mf_decompose_context(	?Version,
				?Conv_id,
				?Origin,
				?Destination,
				?Time_stamp,
				+Context)

	Decompose a contextual-info part into the corresponding
	components.


6.	CCQL Message-core Decomposition

	mf_decompose_ccql_core(	?Performative,
				?Arguments,
				+Core)

	Decompose a CCQL message-core into the corresponding
	CCQL components.



Getting/Setting Argument Value
------------------------------

1.	Get Argument Value

	mf_get_argument(+Source,?Template)


	Get argument value(s) from either a message or an
	argument-list.

	"Source" can be a message (i.e. contextual + core) or an
	argument-list decomposed from a message.
	The matching "Template" can be a "arg:value" pair or
	a list of "arg:value" pairs.


2.	Set Argument Values

	mf_set_argument(+Value_pairs,-Argument_list)

	Create a new argument-list from the "Value_pairs".
	"Value_pairs" can be a single "arg:value" or a list
	in the form: [arg1:value1, arg2:value2, ...]


	mf_set_argument(+Old_args,+Value_pairs,-New_args)

	Update argument value in "Old_args" to give the
	new list "New_args".
	As in mf_set_argument/2, "Value_pairs" can be a single
	"arg:value" pair or a list in the form:
	[arg1:value1, arg2:value2, ...].