SIMSCRIPT II.5 Programming Language

SIMSCRIPT II.5 Programming Language
notices or temporary entities apply. Like event notices, processes and the corresponding process
notices may be defined using the every statement, if user defined attributes are to be declared, or
with the include phrase, if no user attributes are defined. For example:
processes MACHINE.JOB, CHECK.JOB
every ALLOCATE.TRAIN has a NO.OF.CARS, a DESTINATION
In general, characteristics attributed to events or processes may be taken to apply equally to both
unless stated otherwise.
5.2.4 Scheduling Events and Processes
Process and event notices may be filed in the future events set, scheduling their associated routines
for activation at specific instants in future simulation time, using a schedule statement, which has
the general form:
or
schedule an event at time expression
a process at time expression
This statement creates an event or process notice, sets its time.a attribute (the time for which it is
to be scheduled) to the value of the time expression and files the notice in the appropriate event set.
The time expression must evaluate to a real variable or constant. The words activate, reschedule,
and cause are all synonyms for schedule. The word schedule is commonly used
in conjunction with events and activate with processes. These statements are interpreted to
mean:
and
activate a process called variable at time expression
schedule an event called variable at time expression
where process is the name of the process routine variable associated with the entity class. It may
be seen that this is similar to the usage of create and destroy for entities. A schedule statement
may be written with an explicit variable name, as in:
schedule an ARRIVAL called RUSH.ORDER at time expression
If an event or process notice already exists (as a temporary entity, it may have been created previously),
a schedule statement may specify that it be filed in the future events set using the word
this rather than an:
schedule this event called variable at time expression
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