tl;dr:"A string value is not a great type to convey a user's email address or their country of origin. These values deserve much richer and dedicated types. I want a data type called EmailAddress which cannot be null. I want a single point of entry to create a new object of that type. It should get validated and normalised before returning a new value. I want that data type to have helpful methods such as Domain() or NonAliasValue() which would return gmail.com and foo@gmail.com respectively for an input of foo+bar@gmail.com."