diff --git a/src/monger/internal/fn.clj b/src/monger/internal/fn.clj
new file mode 100644
index 0000000..a6e55d6
--- /dev/null
+++ b/src/monger/internal/fn.clj
@@ -0,0 +1,59 @@
+;; Copyright (c) 2011-2012 Michael S. Klishin
+;;
+;; The use and distribution terms for this software are covered by the
+;; Eclipse Public License 1.0 (http://opensource.org/licenses/eclipse-1.0.php)
+;; which can be found in the file epl-v10.html at the root of this distribution.
+;; By using this software in any fashion, you are agreeing to be bound by
+;; the terms of this license.
+;; You must not remove this notice, or any other, from this software.
+
+(ns monger.internal.fn)
+
+
+;;
+;; Implementation
+;;
+
+(defn- apply-to-values [m f]
+  "Applies function f to all values in map m"
+  (into {} (for [[k v] m]
+             [k (f v)])))
+
+
+;;
+;; API
+;;
+
+(defprotocol IFNExpansion
+  (expand-all [x] "Invokes functions, recursively expands maps, evaluates all other values to themselves"))
+
+(extend-protocol IFNExpansion
+  java.lang.Integer
+  (expand-all [i] i)
+
+  java.lang.Long
+  (expand-all [l] l)
+
+  java.lang.String
+  (expand-all [s] s)
+
+  java.lang.Float
+  (expand-all [f] f)
+
+  java.lang.Double
+  (expand-all [d] d)
+
+  java.util.Map
+  (expand-all [m] (apply-to-values m expand-all))
+
+  clojure.lang.PersistentVector
+  (expand-all [v] v)
+
+  clojure.lang.APersistentMap
+  (expand-all [m] (apply-to-values m expand-all))
+
+  clojure.lang.IFn
+  (expand-all [f] (f))
+
+  Object
+  (expand-all [x] x))
diff --git a/test/monger/test/internal/fn.clj b/test/monger/test/internal/fn.clj
new file mode 100644
index 0000000..f76d210
--- /dev/null
+++ b/test/monger/test/internal/fn.clj
@@ -0,0 +1,36 @@
+(ns monger.test.internal.fn
+  (:use [clojure.test]
+        [monger.internal.fn]))
+
+
+(deftest test-recursive-function-values-expansion
+  (are [i o] (is (= (expand-all i) o))
+       { :int (fn [] 1) :str "Clojure" :float (Float/valueOf 11.0)  } { :int 1 :str "Clojure" :float (Float/valueOf 11.0 )}
+       { :long (fn [] (Long/valueOf 11)) } { :long (Long/valueOf 11) }
+       {
+        :i 1
+        :l (Long/valueOf 1111)
+        :s "Clojure"
+        :d (Double/valueOf 11.1)
+        :f (Float/valueOf 2.5)
+        :v [1 2 3]
+        :dyn-i (fn [] 1)
+        :dyn-s (fn [] "Clojure (expanded)")
+        :m { :nested "String" }
+        :dyn-m { :abc (fn [] :abc) :nested { :a { :b { :c (fn [] "d") } } } }
+        }
+       {
+        :i 1
+        :l (Long/valueOf 1111)
+        :s "Clojure"
+        :d (Double/valueOf 11.1)
+        :f (Float/valueOf 2.5)
+        :v [1 2 3]
+        :dyn-i 1
+        :dyn-s "Clojure (expanded)"
+        :m { :nested "String" }
+        :dyn-m {
+                :abc :abc
+                :nested { :a { :b { :c "d" } } }
+                }
+        }))