Amulet Syntax

• Defining a Chare
• Defining a Message
• Creating an Instance of a Chare
• Creating an Instance of a Message
• Sending a Message
• Creating and Sending a Message
• Initializing the Amulet Application

Defining a Chare

Chare( chare_type )
	type1	fieldname1;
	type2	fieldname2;
	  .         .		/* declarations of the fields associated with
	  .	    .		   this chare */
	  .	    .		
	typeN	fieldnameN;

Entries{ entry_name1, entry_name2, ..., entry_nameN };
	
Code( chare_type )

	Entry( entry_name1, message_type )
		
		C Code specific to this entry
		
	EndEntry;
	
	Entry( entry_name2, message_type )
	
		C Code specific to this entry
		
	EndEntry;
		.
		.
		.
	Entry( entry_nameN, message_type )
	
		C Code specific to this entry
		
	EndEntry;
	
EndChare;

entry_name: The name used to identify an entry point of a chare.

message_type: The name of the type of message that can be received by an entry. Only one type of message can be received by any particular entry of a chare.

Note: Use 'chr' for referencing the chare within its own code and use 'msg' for referencing the message received by an entry.
For example, the line 'chr->times = 3;' could be contained in one (or more) of a particular chare's entries. This would set the times field of the chare equal to 3. Likewise, the line 'chr->value = msg->count' would set the value field of the chare equal to the count field of the received message.

Defining a Message

Message( message_type )
	type1	fieldname1;
	type2	fieldname2;
	  .         .		/* declarations of the fields associated with
	  .	    .		   this message */
	  .         .
	typeN	fieldnameN;
EndMessage;

Creating an Instance of a Chare

CreateChare( chare_name, chare_type );

chare_type: The type of chare to create. Remember CreateChare is used to declare an instance of a chare. The actual chare type (chare class) is defined by the Chare...EndChare structure.

Note: The CreateChare macro causes a declaration, so it must occur at the beginning of any C code block.

Creating an Instance of a Message

CreateMsg( message_name, message_type );

chare_type: The type of message to create. Remember CreateMsg is used to declare an instance of a message. The actual message type (message class) is defined by the Message...EndMessage structure.

Note: The CreateMsg macro causes a declaration, so it must occur at the beginning of any C code block.

Sending a Message

There are two Amulet macros used for sending a previously created message: SendMsgNow and SendMsgLater. The SendMsgNow macro submits the given message to be delivered as soon as possible. The SendMsgLater macro submits the message to be delivered at a later time.

SendMsgNow( message_name, chare_name, entry, deadline_time );

SendMsgLater(  message_name, chare_name, entry, begin_time, end_time );

chare_name: The name of the chare the message is to be sent to.

entry: The entry of the specified chare that the message should be directed to.

deadline_time: The time the message must be sent by. This parameter must be of type timetyp.

begin_time: The earliest the message may be delivered. This parameter must be of type timetyp.

end_time: The latest the message may be delivered. This parameter must be of type timetyp.

Creating and Sending a Message

If it is necessary to send a message not previously created, it is possible to create and send a message with one of two macros: SendNow and SendLater. The SendNow macro creates a message and submits it to be delivered as soon as possible. The SendLater macro also creates a message but submits it to be delivered at a later time.

SendNow( message_type, chare_name, entry, deadline_time )

	C Code for setting message fields
	
EndSendNow;

SendLater(  message_type, chare_name, entry, begin_time, end_time )

	C Code for setting message fields
	
EndSendLater;

chare_name: The name of the chare the message is to be sent to.

entry: The entry of the specified chare that the message should be directed to.

deadline_time: The time the message must be sent by. This parameter must be of type timetyp.

begin_time: The earliest the message may be delivered. This parameter must be of type timetyp.

end_time: The latest the message may be delivered. This parameter must be of type timetyp.

Note: Use 'm' for referencing the message to be sent.
For example, the line 'm->total = 5;' could be contained in the C code for setting the total field of the message that will be created and sent.

Initializing the Amulet Application

AmuletInit

	C Code for initializing the process
	
EndAmuletInit;