1. For a structured markup language document having a plurality of data entry fields each corresponding to a markup language node, wherein the markup language nodes are arranged in a hierarchical structure of parent nodes having child nodes and wherein the hierarchical position of each said markup language node in the hierarchical structure is expressed as a corresponding fragment of the markup language, a method comprising, for each said parent node: forming a markup language fragment having a plurality of portions each corresponding to the fragment of a respective said child node without repeating any said fragment of a respective said child node; and using the portions of the markup language fragment respectively corresponding to the child nodes for data entry with the data entry fields, wherein: the structured markup language document has a syntax described by a schema; the electronic form definition document encodes schema information from the schema to achieve schema awareness at edit time; and using the portions further comprises using the form definition document having the markup language fragment and the schema information at edit time to determine for each data entry field a corresponding said portion of the maximal information fragment to perform data entry for the data entry field, such that data entry for each said data entry field is valid with respect to the schema.