Reducers, transducers and core.async in Clojure(eli.thegreenplace.net)

    process = pipeline(partial(filter, even), 
                       partial(map, inc), 
                       sum)
    
    process(some-iterable)

    (def process [xs]
      (->> xs
           (filter even?)
           (map inc)
           (reduce +)))
    
    (process some-iterable)

    (def process 
      (pipeline
          (partial filter even?)
          (partial map inc)
          (partial reduce +)))

     process(some-iterable)
    

    def pipeline(*fns):
        return reduce(lambda f, g: lambda *xs, **ys: g(f(*xs, **ys)), fns)

    (defn pipeline [& fs] (apply compose (reverse fs)))

  import operator

  formulas = {
    'sum': operator.add,
    'subst': operator.sub,
    'mult': operator.mul,
    'pow': operator.pow
  }