SIMSCRIPT II.5 Programming Language

SIMSCRIPT II.5 Programming Language
Table 4-2. Required Set Attributes
Statement
Attributes Required
F L P S M N
file in a ranked set x x
file first x x
file last x x x
file before x x x
file after x x
remove first x x
remove last x x x x
remove specific x x x
is empty
x
is in set
Automatic checking †
x
x
for each V in set x x
for each V in set in rev. x x
for each v from W in set
x
for each V from W in set in rev.
x
for each V after W in set
x
for each V after W in set in rev.
x
†
Following sections describe automatic set diagnostics performed only when a
membership attribute is included.
4-10. Common Attributes
An entity is characterized by its attributes. The attributes with which it is declared determine the
values it can hold and the relationships it can have with other entities. Sometimes it is desirable that
more than one entity type be able to have some characteristics in common, although the entity types
may be different in other ways. By declaring that a number of different entity types have certain
common attributes, it becomes possible to treat them all in the same way for some "generic" operations.
An example of such a common attribute declaration is:
every TANKER has a SPEED, a CARGO,
and belongs to the HARBOR.SET
every TUG has a SPEED
and belongs to the HARBOR.SET
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