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+;;  Copyright (c) Stephen C. Gilardi. All rights reserved.  The use and
+;;  distribution terms for this software are covered by the Common Public
+;;  License 1.0 (http://opensource.org/licenses/cpl.php) which can be found
+;;  in the file CPL.TXT 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.
+;;
+;;  File: cond.clj
+;;
+;;  scgilardi (gmail)
+;;  2 October 2008
+
+(ns clojure.contrib.cond)
+
+(defmacro cond-let
+  "Takes a binding-form and a set of test/expr pairs. Evaluates each test
+  one at a time. If a test returns logical true, cond-let evaluates and
+  returns expr with binding-form bound to the value of test and doesn't
+  evaluate any of the other tests or exprs. To provide a default value
+  either provide a literal that evaluates to logical true and is
+  binding-compatible with binding-form, or use :else as the test and don't
+  refer to any parts of binding-form in the expr. (cond-let binding-form)
+  returns nil."
+  [binding-form & clauses]
+  (when-let [[test expr & more] clauses]
+    (if (= test :else)
+      expr
+      `(if ~test
+         (let [~binding-form ~test] ~expr)
+         (cond-let ~binding-form ~@more)))))