gistfile1.clj

(use 'clojure.walk)

;from psykotic http://gist.github.com/328830
(defmacro >> [& xs]
  (reduce (fn [x1 x2]
            (let [x1- (gensym)]
              `(let [~x1- ~x1]
                 ~(postwalk (fn [x] (if (= x '%) x1- x)) x2))))
          (macroexpand-all xs)))

;allows forms that are not lists (>> 5 (+ 1 %) print) -> (print (+ 1 5))
(defmacro >> [& xs]
  (reduce (fn [x1 x2]
	    (if (seq? x2)
	      (let [x1- (gensym)]
		`(let [~x1- ~x1]
		   ~(postwalk (fn [x] (if (= x '%) x1- x)) x2)))
	      (list x2 x1)))
          (macroexpand-all xs)))

;nilsafe >>
(defmacro >?> [& xs]
  (reduce (fn [x1 x2]
	    (cond
	     (nil? x1) nil
	     (seq? x2)
	     (let [x1- (gensym)]
	       `(let [~x1- ~x1]
		  ~(postwalk (fn [x] (if (= x '%) x1- x)) x2)))
	     :else (list x2 x1)))
          (macroexpand-all xs)))