This new sample shows how to create an arithmetic expression evaluator, so the application can evaluate a formula such as:

((a + b) ^(c / d)) * e

or

a + b + c * (d - e)

There some limitations due the way the parser was built:

. Only one letter variables are supported
. There is no numeric literal support. All values must be hold in variables
. Variables are case sensitive (a <> A)

The OO Cobol code is an improved version of Partha Kuchana Java Calculator sample : http://www.java2s.com/Code/Java/Design-Pattern/InterpreterPatternCalculator.htm

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