SIMSCRIPT II.5 Programming Language

SIMSCRIPT II.5 Programming Language
move from arithmetic expression
The value of the arithmetic expression is stored in the variable referenced by the routine name and
its arguments, if any. For example, EXAMPLE(I,J). The form of a typical left-handed monitoring
routine is:
left function EXAMPLE(I,J)
enter with Q
.
.
statements using I,Q
.
.
move from expression
end
A value is transmitted to the function by the enter statement, computations are performed, and a
value is assigned to the monitored variable by the move statement.
The following short programs use monitored variables in several different ways for data editing,
where the monitored variable feature provides two important benefits: (1) It keeps the main body
of the program clear of data-checking and message printing statements, making it easier to understand;
and (2) Conversion of the program to remove the editing feature can be accomplished by
changing only one preamble statement and discarding two routines, with the main body of the program
text unchanged. However, the program must be recompiled.
This program first reads successive sets of data representing subscript values for a two-dimensional
array and the associated data value. The subscripts are checked by the left-monitoring routine before
values are assigned. Default values are computed for any unassigned values. The initialization
data are delimited by a single non-numeric field, and followed by query data, requesting the value
identified by two given subscripts. These subscripts are also checked, this time by the right-monitoring
routine.
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