2. Lists - Koans Walkthrough

This video covers the fundamental data structure of Lisp and Clojure: lists. Lisp stands for "LISt Processing", after all!

Here is the 02_lists.clj source code:

  "Lists can be expressed by function or a quoted form"
  (= '(__ __ __ __ __) (list 1 2 3 4 5))

  "They are Clojure seqs (sequences), so they allow access to the first"
  (= __ (first '(1 2 3 4 5)))

  "As well as the rest"
  (= __ (rest '(1 2 3 4 5)))

  "The rest when nothing is left is empty"
  (= __ (rest '(100)))

  "And construction by adding an element to the front is simple"
  (= __ (cons :a '(:b :c :d :e)))

  "Conjoining an element to a list can be done in the reverse order"
  (= __ (conj '(:a :b :c :d :e) 0))

  "You can use a list like a stack to get the first element"
  (= __ (peek '(:a :b :c :d :e)))

  "Or the others"
  (= __ (pop '(:a :b :c :d :e)))

  "But watch out if you try to pop nothing"
  (= __ (try
          (pop '())
          (catch IllegalStateException e "No dice!")))

  "The rest of nothing isn't so strict"
  (= __ (try
          (rest '())
          (catch IllegalStateException e "No dice!"))))

Clojure Koans Walkthrough in Light Table IDE

This screencast tutorial helps you learn the Clojure programming language. Experience the joy of Clojure in the Light Table IDE as we tour through the Clojure Koans, taking you all the way from Beginner to Intermediate to Advanced.

Clojure is a Lisp created by Rich Hickey that runs on the JVM, as an alternative to Java. ClojureScript can target the web browser environment, and node.js, by compiling down to JavaScript, using the Google Closure compiler. Clojure features immutability, functional programming, and being a Lisp, macros.