SIMSCRIPT II.5 Programming Language

Modelling Concepts
F.KENNEL
L.KENNEL
N.KENNEL
FARM
3
LICENSE
P.KENNEL
S.KENNEL
M.KENNEL
1 2 3
0
0
LICENSE
248
P.KENNEL
S.KENNEL
M.KENNEL 0
LICENSE
DOG
567
P.KENNEL
S.KENNEL
0
M.KENNEL 0
Figure 4-16. Entity Records
Entities are removed from sets by remove statements. Two basic forms of removal are possible.
1a. remove first variable from set
1b. remove last variable from set
2. remove arithmetic expression from set
The word the is optional after remove, as is either of the words the and this before the set name.
In addition, either of the words this or above can be used before the expression in form (2).
A remove first or remove last statement removes from a set the entity pointed to by the first
or last pointer attribute of the set owner. The identification number of the removed entity is assigned
to the variable in the remove statement. For instance, in the situation shown in figure 4-19,
the statement:
remove the first HOUND from KENNEL(FARM)
removes the first entity (MYDOG) from KENNEL(FARM), makes the second entity first, and puts a
pointer to MYDOG in HOUND. The attribute values of MYDOG, which now can also be called HOUND,
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