Class ExpValue

MathParser/src/com/aghajari/math/MathParser.java:978–989

A new ExpValue means parser once tried to calculate ExpValue#expression but something went wrong! (usually a variable is missed), So Parser tries to store the expression in a ExpValue and calculate it again when needed by MathParser#calculate and will set fromExpValue true, i

     * that's why we use {@link ExpValue}, to make sure there won't be any dynamic variable.
     */
    private static class ExpValue {
        final String expression, original;

        ExpValue(String expression, String original) {
            this.expression = expression;
            this.original = original;
        }

        public double calculate(MathParser parser) throws MathParserException {
            return parser.calculate(expression, original, true);
        }
    }

    /**
     * A simple parser to parse a linear expression,