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Ch 4. Evaluating Expressions [ Command Interpreter Access and Variables Programmer's Guide ] MPE/iX 5.0 Documentation

Command Interpreter Access and Variables Programmer's Guide

Chapter 4  Evaluating Expressions 

Expression results can be used to define complex functions.  They form
the basis of comparison structures in establishing branches and loops.
Expressions can also be used to set variables based on an equation of
predefined variables, user-defined variables, constants, and arithmetic
or logical operators.

MPE/iX 5.0 Documentation