clojure-koans/07_functions.clj

32 lines
816 B
Clojure

; "Calling a function is like giving it a hug with parentheses"
(= __ (square 9))
; "Functions are usually defined before they are used"
(= __ (multiply-by-ten 2))
; "But they can also be defined inline"
(= __ ((fn [n] (* 5 n)) 2))
; "Or using an even shorter syntax"
(= __ (#(* 15 %) 4))
; "Even anonymous functions may take multiple arguments"
(= __ (#(+ %1 %2 %3) 4 5 6))
; "Arguments can also be skipped"
(= __ (#(* 15 %2) 1 2))
; "One function can beget another"
(= 9 (((fn [] ___)) 4 5))
; "Functions can also take other functions as input"
(= 20 ((fn [f] (f 4 5))
___))
; "Higher-order functions take function arguments"
(= 25 (___
(fn [n] (* n n))))
; "But they are often better written using the names of functions"
(= 25 (___ square))