clojure-koans/src/koans/14_destructuring.clj
Colin Jones 04b3c4a960 Bump koan-engine dependency
Also eliminates some ns forms that we can do without now.

Closes #71
2014-05-02 16:39:13 -05:00

45 lines
1.3 KiB
Clojure

(ns koans.14-destructuring
(:require [koan-engine.core :refer :all]))
(def test-address
{:street-address "123 Test Lane"
:city "Testerville"
:state "TX"})
(meditations
"Destructuring is an arbiter: it breaks up arguments"
(= __ ((fn [[a b]] (str b a))
[:foo :bar]))
"Whether in function definitions"
(= (str "First comes love, "
"then comes marriage, "
"then comes Clojure with the baby carriage")
((fn [[a b c]] __)
["love" "marriage" "Clojure"]))
"Or in let expressions"
(= "Rich Hickey aka The Clojurer aka Go Time aka Macro Killah"
(let [[first-name last-name & aliases]
(list "Rich" "Hickey" "The Clojurer" "Go Time" "Macro Killah")]
__))
"You can regain the full argument if you like arguing"
(= {:original-parts ["Stephen" "Hawking"] :named-parts {:first "Stephen" :last "Hawking"}}
(let [[first-name last-name :as full-name] ["Stephen" "Hawking"]]
__))
"Break up maps by key"
(= "123 Test Lane, Testerville, TX"
(let [{street-address :street-address, city :city, state :state} test-address]
__))
"Or more succinctly"
(= "123 Test Lane, Testerville, TX"
(let [{:keys [street-address __ __]} test-address]
__))
"All together now!"
(= "Test Testerson, 123 Test Lane, Testerville, TX"
(___ ["Test" "Testerson"] test-address)))