gistfile1.clj

(defmacro remote-declare [name]
  "declares the supplied ns-qualified name with no bindings, useful for creating circular dependencies"
  (let [[ns v] (.split (str name) "/")
        orig-ns (str *ns*)]
    `(do (in-ns '~(symbol ns))
         (clojure.core/declare ~(symbol v))
         (in-ns '~(symbol orig-ns)))))

user> (remote-declare tmp8/a)
#<Namespace user>
user> (defn a[] (tmp8/a))
#'user/a
user> (a)
; Evaluation aborted.
user> *e
#<CompilerException java.lang.IllegalStateException: Var tmp8/a is unbound. (NO_SOURCE_FILE:0)>
user> (ns tmp8)
nil
tmp8> (use 'clojure.core)
nil
tmp8> (defn a [] :a)
#'tmp8/a
tmp8> (ns user)
nil
user> (a)
:a