clojure_lesson_1

Namespace

(ns learnclojure)

Types

(type 1)
(type 1.1)
(type true)
(type "Hello")
(type (keyword "a"))

(type (quote a))
(type 'a)
(type (list 1 2 3))
(type (vector 1 2 3))
(nth (vector 1 2 3) 2)

(last (list 1 2 3))

List
(type (list 1 2 3))
(type (vector 1 2 3))

Map
{:a 1 :b 1 :c 1} {:a 1, :b 1, :c 1}
(hash-map :a 1 :b 1 :c 1)

Set
{type #{1 2 3}}
(hash-set 1 2 3)

=========================================================


Control Flow

//define var with value
(def x "Hello")

(if (empty? x)
   "x is empty"
   "x is not empty")

(if (empty? x)
   nil
   (do
      (println "ok")
       :ok))
       
       
(if-not (empty? x)
   (do
      (println "ok")
      :ok))
      
(when (not (empty? x)) :ok)

(case x
   "Goodby": goodbye
   "Hi": hello
   :nothing)
   
(cond
  (= x "Goodbye") :goodbye
  (- (reverse x) "olleH") :olleh
  :otherwise :nothing)
  

==============================================

Functions

(def hello (fn [] "Hello"))

(hello)

#(str "Helo)

(defn hello [] "Hello")

(defn hello [name] (str "Hello, " name))
(defn hello "Greets a person named <name> with their <title>" [name, title] (str "Hello, " title " " name))

(require '[clojure.repl :refer [doc]])
(doc hello)