1. A system that maps an anonymous first construct of a markup language domain to a second construct of an object oriented language domain comprising a computer-readable storage medium, comprising the following computer-executable components: a bank that stores a set of introduce field labels identifying object oriented language constructs that are created to represent anonymous markup language constructs when the anonymous markup language constructs are deserialized into the object oriented language constructs, and a set of suppress field labels identifying the introduce field labels that are to be removed during serialization of the object oriented language constructs to the anonymous markup language constructs; and a mapping component that, during deserialization of a markup language document that contains an anonymous first construct, maps the anonymous first construct of the markup language document to a named second construct in an object oriented language domain by assigning one of the introduce field labels in the bank to represent the anonymous first construct in the object domain, and that, during subsequent serialization of the named second construct in the object oriented language domain to a markup language document in the markup language domain, removes the introduce field label to create the anonymous first construct in the serialized markup language document in the markup language domain.