FIFO puts the message at the end of the IL of a L type node

Syntax:

    FIFO;

It is used to add a message to the end of the IL of a L type node. The first message in the EL of the L type node is passed to the end of the IL. The IL is formed in the order of arrival (FIFO order). As this order is the same that the default order in which the EL is processed, the FIFO procedure can be omitted unless other order specifications are also used in the same node.

It may be used only in L type nodes.

Example:

  LinePile :: IF Box THEN LIFO ELSE FIFO

Messages, that have the field Box equal to TRUE, are added at the beginning of the IL; the others at the end (see FIFO procedure, 7.9). When they are extracted from the IL in the order of this list those with Box = TRUE are extracted in LIFO order (that who came last is extracted first) as in a pile of boxes. After these are the messages with Box = FALSE ordered as they arrived.