Skip to content

Instantly share code, notes, and snippets.

What would you like to do?
Clojure ns syntax cheat-sheet
;; * :require makes functions available with a namespace prefix
;; and optionally can refer functions to the current ns.
;; * :import refers Java classes to the current namespace.
;; * :refer-clojure affects availability of built-in (clojure.core)
;; functions.
;; Updated: 7/9/2014 ~ghoseb
;; Refers clojure.contrib.math into current NS, e.g.:
;; (clojure.string/lower-case "FooBar)
(:require [clojure.string])
;; Refers math into current NS, e.g.:
;; (string/lower-case "FooBar")
(:require [clojure.string :as string])
;; Refers all functions from clojure.contrib.math and
;; clojure.contrib.seq-utils into current NS, e.g.:
;; (union #{:a :b} #{:a :c} #{:b :d})
;; (lower-case "FooBar")
(:require [clojure.string :refer :all]
[clojure.set :refer :all])
;; Refers only sqrt and flatten into current NS, e.g.:
;; (union #{:a :b} #{:a :c} #{:b :d})
;; (lower-case "FooBar")
(:require [clojure.string :refer [lower-case]]
[clojure.set :refer [union]])
;; Refers ancestors & descendants into current NS as xml-ancestors & xml-descendants
(:refer [ :rename {ancestors xml-ancestors,
descendants xml-descendants}])
;; Refers ArrayList and HashMap into current NS:
(:import [java.util ArrayList HashMap])
;; Excludes built-in print
(:refer-clojure :exclude [print])
;; Excludes all built-ins except print
(:refer-clojure :only [print])
;; Renames built-in print to core-print
(:refer-clojure :rename {print core-print})
;; Reload all dependencies while loading the ns
(:require [clojure.string :as cs :refer [split join]] :reload)
;; Be verbose about loading the deps
(:require [clojure.string :as cs :refer [split join]] :verbose)
;; There is also :reload-all that reloads every depenency in the ns
(:require [clojure.string :refer [split join]] :reload-all)
;; Everything together
(:require [clojure.string :as cs :refer [split join]] :verbose :reload))
Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment