SIMSCRIPT II.5 Programming Language

Modelling Concepts
VESSEL
V(I)
NAME
TONNAGE
NAME
TONNAGE
Figure 4-8. Entity Creation
If desired, the words a or an can be used after create to improve readability, as in:
create a SHIP called QUEEN.MARY
create an EVENT called BIRTH
If no variable is specified in a called clause, the entity identification number is assigned to the
global variable with the same name as the entity class. Recall that the every statement implicitly
declares a global pointer variable with the same name as the entity class. The statement:
create a SHIP
allocates space for a SHIP entity, and assigns the pointer value to the automatically defined global
variable named SHIP. It is interpreted as if written:
create a SHIP called SHIP
The attributes of a particular instance of a temporary entity are referenced using the notation:
as in:
and:
attribute name(identification number)
NAME(VESSEL)
TONNAGE(QUEEN.MARY)
Because attribute references refer to locations in memory, like variable names, they can be used in
the same way that variables are used — in input/output lists and in logical and arithmetic expressions.
For example:
145