public void CharactersRangeRegex()
        {
            dynamic se = new SimpleExpression();
            SimpleExpression result = se
                .OneOf("a|z")
                .Generate();

            Assert.AreEqual(@"(a|z)", result.Expression);
        }
        public void SimpleRepetitionTests()
        {
            dynamic se = new SimpleExpression();
            Assert.AreEqual("[0-9]{2,}", se.Numbers.AtLeast(2).Generate().Expression);

            se = new SimpleExpression();
            Assert.AreEqual("[a-zA-Z]{2,}", se.Letters.AtLeast(2).Generate().Expression);

            se = new SimpleExpression();
            Assert.AreEqual("[a-zA-Z0-9]{2,}", se.Alphanumerics.AtLeast(2).Generate().Expression);

            se = new SimpleExpression();
            Assert.AreEqual("a{2,}", se.One("a").AtLeast(2).Generate().Expression);

            se = new SimpleExpression();
            Assert.AreEqual("(a|b|cd){2,}", se.OneOf("a|b|cd").AtLeast(2).Generate().Expression);

            se = new SimpleExpression();
            Assert.AreEqual("(a|b|cd){2,}", se.EitherOf("a|b|cd").AtLeast(2).Generate().Expression);

            se = new SimpleExpression();
            Assert.AreEqual("([0-2]|3){2,}", se.NumberInRange("0-3").AtLeast(2).Generate().Expression);

            se = new SimpleExpression();
            Assert.AreEqual("[a-cA-C]{2,}", se.LetterInRange("a-c").AtLeast(2).Generate().Expression);

            se = new SimpleExpression();
            Assert.AreEqual("([a-zA-Z]*){2,}", se.Group.AtLeast(2).Letters.Together.Generate().Expression);

            se = new SimpleExpression();
            Assert.AreEqual("(?<letters>[a-zA-Z]*){2,}", se.Group.AtLeast(2).Letters.Together.As("letters").Generate().Expression);

            se = new SimpleExpression();
            Assert.AreEqual("[a-zA-Z~]{2,}", se.Letters.And("~").AtLeast(2).Generate().Expression);

            se = new SimpleExpression();
            Assert.AreEqual("[a-zA-Z-[zZ]]{2,}", se.Letters.Except("z").AtLeast(2).Generate().Expression);
        }