Contextual Query Language is defined by the Library of Congress. I discovered it via CQL::Parser. Brian Cassidy is involved, so it must be good.
I immediately thought “oh shit. Now my new Search::Query module feels late-to-the-party.” But on further reading, I think a CQL dialect in Search::Query makes some sense.
Search::Query is a SQL::Translator-like module for free-text search. I coded it up this week after brewing the idea for some many months. I’m imagining it now as a next-generation Search::QueryParser::SQL, for contexts beyond SQL. Example: I have a query string that works with Xapian and want to convert it to one that works with Swish-e 2.x or KinoSearch. Just parse it with Search::Query::Parser and assign it a target dialect and then call $query->stringify to get the translated version out.