1. A computing system that has access to a hierarchically-structured document having a plurality of elements that may each be associated with one or more namespaces, the computing system comprising: one or more computer-readable storage media having computer-executable instruction for implementing a method for establishing a plurality of abbreviated namespace identifiers for a hierarchically-structured document, wherein the method comprises: an act of associating each of a plurality of hierarchical namespaces with an associated abbreviated namespace identifier; an act of accessing a hierarchically-structured document; an act of determining that at least one group identifier is associated with the hierarchically-structured document, the group identifier representing that when any of the abbreviated namespace identifiers are found associated with an element in the hierarchically-structured document, that the associated namespace is also associated with that element; and at least one of: an act of associating each of the plurality of hierarchical namespaces with the associated abbreviated namespace identifier before the act of accessing the hierarchically-structured document, and an act of reading a pre-processor directive that indicates that the at least one group identifier is associated with the hierarchically-structured document.