(defn square [x] (* x x)) (meditations "One may know what they seek by knowing what they do not seek" (= [__ __ __] (let [not-a-symbol? (complement symbol?)] (map not-a-symbol? [:a 'b "c"]))) "Praise and 'complement' may help you separate the wheat from the chaff" (= [:wheat "wheat" 'wheat] (let [not-nil? ___] (filter not-nil? [nil :wheat nil "wheat" nil 'wheat nil]))) "Partial functions allow procrastination" (= 20 (let [multiply-by-5 (partial * 5)] (___ __))) "Don't forget: first things first" (= [__ __ __ __] (let [ab-adder (partial concat [:a :b])] (ab-adder [__ __]))) "Functions can join forces as one 'composed' function" (= 25 (let [inc-and-square (comp square inc)] (inc-and-square __))) "Have a go on a double dec-er" (= __ (let [double-dec (comp dec dec)] (double-dec 10))) "Be careful about the order in which you mix your functions" (= 99 (let [square-and-dec ___] (square-and-dec 10))))