public void ParseSimpleArithmeticOperation_ExpectSimpleArithmeticExpressionObject()
        {
            string[] simpleExpression = new string[] { "2 +  1" };
            var      resp             = _parseExpressions.Parse(simpleExpression[0]);

            Assert.IsInstanceOf <SimpleArithmeticExpression>(resp);
        }
        private async Task <ExpressionResponse> ReturnExpressionResults(string[] expressions, int?precision)
        {
            //First we Parse the expression to get the object that will evaluate the expression.
            var expressionType = _parseExpressions.Parse(expressions[0]);
            var resp           = await expressionType.CalculateResult(expressions, precision);

            return(resp);
        }