Dynamic scoping in action!

dynamic_scoping.clj

(def ^:dynamic *current-tree-name*)

(defn record-adjunct
  "Records an adjunction performed by our rules."
  [phrase adjunct]
  (swap! adjunctions conj {:name *current-tree-name*
                           :phrase phrase
                           :adjunct adjunct}))

(def fixed-trees
  "A map from tree filenames to their fixed versions."
  (into {} (for [[name tree] trees]
             (binding [*current-tree-name* name]
               [name (fix-tree tree)]))))