(defn find-namespaces
"Searches a sequence of java.io.File objects (both directories and
JAR files) for .clj or .cljc source files containing (ns...) declarations.
Returns a sequence of the symbol names of the declared
namespaces. Use with clojure.java.classpath to search Clojure's
classpath."
[files]
(map second (find-ns-decls files)))