+=item ZOOM::Query::CCL2RPN
+
+Implements CCL by compiling it on the client-side into a Z39.50 Type-1
+(RPN) query, and sending that. Because the compilation is done on the
+client side, a configuration file is required to direct the mapping of
+CCL constructs such as index names and boolean operators into Type-1
+query attributes. An example CCL configuration file is included in
+the ZOOM-Perl distribution, in the file C<samples/ccl/default.bib>
+
+CCL is syntactically very similar to CQL, but much looser. While CQL
+is an entirely precise language in which each possible query has
+rigorously defined semantics, and is thus suitable for transfer as
+part of a protocol, CCL is best deployed as a human-facing UI
+language.
+