1. One or more computer-readable media embodying computer-readable instructions which, when executed, perform acts comprising: receiving a selection of at least part of a graphical rendering of a hierarchically structured electronic document; receiving a structured-document path-language address usable to locate the part of the hierarchically structured electronic document; automatically producing a simplified form of the structured-document path-language address, the simplified form of the structured-document path-language address being produced by abbreviating the structured-document path-language address by removing one or more unique namespaces; and building a structured-document path-language expression that includes the structured-document path-language address and, if the part of the hierarchically structured electronic document includes a blank value, altering the structured-document path-language expression to treat the blank value as a zero.