clojure notes

gistfile1.clj

(defn hello [name] (str "Hello, " name))

gistfile2.txt

defn - function
hello - function name
hello - takes one argument, name
str - is a function call that concatenates an arbitrary list of arguments into a string
defn, hello, name, and str are all symbols

gistfile3.clj

;; {}

;; Conjoin, build a new collection
(conj coll item)
(conj #{} "Mike")

;; Atom
(atom initial-state)

;; Name Atom
(def symbol initial-value?)
(def visitors (atom #{}))

;; Update Ref
(swap! r update-fn & args)
(swap! visitors conj "Mike")

;; Refs
(deref visitors)
@visitors

gistfile4.clj

;; require a library
(require quoted-namespace-symbol)
(require 'clojure.java.io)

;; refer namespace to call libs directly
(refer `examples.introduction)

;; require and refer together
(use quoted-namespace-symbol)
(use 'examples.introduction)
(take 10 fibs)

;; reload, force library to reload
(use :reload 'examples.introduction)

gistfile5.txt

a - a Java array
agt - an agent
coll - a collection
expr - an expression
f - a function
idx - index
r - a ref
v - a vector
val - a value

reserved: ref, agent, count

gistfile6.txt

number -> 42
vector -> [1 2 3]
list -> (+ 1 3) -> 4

boolean - true, false
character - \a
keyword - :tag, :doc
list - (1 2 3), (println "foo")
map - {:name "Bill", :age 42}
nil - nil
number - 1, 4.2
set - {:snap, :crackle, :pop}
string - "hello"
symbol - user/foo, java.lang.String
vector - [1 2 3]