1.1 --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
     1.2 +++ b/src/clojure/contrib/generic/functor.clj	Sat Aug 21 06:25:44 2010 -0400
     1.3 @@ -0,0 +1,40 @@
     1.4 +;; Generic interface for functors
     1.5 +
     1.6 +;; by Konrad Hinsen
     1.7 +;; last updated May 3, 2009
     1.8 +
     1.9 +;; Copyright (c) Konrad Hinsen, 2009. All rights reserved.  The use
    1.10 +;; and distribution terms for this software are covered by the Eclipse
    1.11 +;; Public License 1.0 (http://opensource.org/licenses/eclipse-1.0.php)
    1.12 +;; which can be found in the file epl-v10.html at the root of this
    1.13 +;; distribution.  By using this software in any fashion, you are
    1.14 +;; agreeing to be bound by the terms of this license.  You must not
    1.15 +;; remove this notice, or any other, from this software.
    1.16 +
    1.17 +(ns
    1.18 +  ^{:author "Konrad Hinsen"
    1.19 +     :doc "Generic functor interface (fmap)"}
    1.20 +  clojure.contrib.generic.functor)
    1.21 +
    1.22 +
    1.23 +(defmulti fmap
    1.24 +  "Applies function f to each item in the data structure s and returns
    1.25 +   a structure of the same kind."
    1.26 +   {:arglists '([f s])}
    1.27 +   (fn [f s] (type s)))
    1.28 +
    1.29 +(defmethod fmap clojure.lang.IPersistentList
    1.30 +  [f v]
    1.31 +  (into (empty v) (map f v)))
    1.32 +
    1.33 +(defmethod fmap clojure.lang.IPersistentVector
    1.34 +  [f v]
    1.35 +  (into (empty v) (map f v)))
    1.36 +
    1.37 +(defmethod fmap clojure.lang.IPersistentMap
    1.38 +  [f m]
    1.39 +  (into (empty m) (for [[k v] m] [k (f v)])))
    1.40 +
    1.41 +(defmethod fmap clojure.lang.IPersistentSet
    1.42 +  [f s]
    1.43 +  (into (empty s) (map f s)))