For my sins I have been trying to rationalize our internal proximity search representations, and thought comparison with CQL would be instructive. I finally found "prox" as a Boolean operator (not my choice, but that is not the issue here). To be sure I understood things I went through the definitions and then the examples. All was well until the very last example on the very last page (ok, the second page – but the last one).
So at http://www.loc.gov/standards/sru/resources/cql-context-set-v1-2.html is the example:
zeerex.set = cql prox/unit=element/distance=0 zeerex.index = resultSetId
Find the cql context set in the same element as the index name resultSetId. E.g. search for cql.resultSetId
My reading suggests this is a search for "cql.zeerex.index", not "cql.resultSetId". If the example is correct as it stands could somebody explain how/why. And also explain why the example has "zeerex.set =" on the beginning and "= resultSetId" on the end, when these really have nothing to do with the "unit=element/distance=0" that the example is trying to clarify. This is the only example so encumbered, and it has, obviously, managed to confuse me.