When declaring an element that has simple content, you start with a basic element declaration:
Within the element declaration, you include a declaration in which you specify that you want your element to have simple content.
You do this by creating a declaration that contains a element.
The element indicates that the cannot contain child elements.
It may contain attributes, but otherwise the content will be defined by a simple type.
Within the element, you can create an declaration.
You must use an declaration because you will be extending an existing data type by adding attribute declarations.
Any of the following examples are allowable elements based on the previous declaration:
001-909-555-1212
001-909-555-1212