Narrowed Extended XPath I
NEXI is an information retrieval (IR) query language for searching structured and semi-structured document collections. The language was first introduced for searching XML documents at the annual INEX  evaluation forum in 2004, and it was used extensively by INEX for its element retrieval and XML-IR experiments.
Designed as the simplest query language that could possibly work, the language is a tiny subset of XPath 1.0  with an added about() function for identifying elements about some given topic. The language has extensions for question answering, multimedia searching, and searching heterogeneous document collections. NEXI is a language with a strict syntax defined in YACC but it has no semantics; the interpretation of the query is the task of the search engine.
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