ClojureScript

Google Closure Library

ClojureScript projects always auto-include the Google Closure Library, a massive library built and used by Google on many of their products (Gmail, Docs, etc). It has low-level utilities for DOM manipulation, server communication, animation, data structures, unit testing, rich-text editing, and UI widgets/controls.

Try the wrapper libraries first!

You may first want to consider the following ClojureScript libraries which wrap some functionality from Google Closure Library. Their source code also serves as good examples of how to use Closure directly.

ClojureScript wrapper Closure Libraries

cljs-time

goog.date

cljs-http

goog.net, goog.uri

cljs-ajax

goog.net, goog.uri, goog.json

cuerdas

goog.string

* included in ClojureScript’s core library

Using Google Closure directly

Some helpful blog posts:

To use Google Closure in your ClojureScript code, the rule is to use:

  • :import for Closure classes (which are also namespaces, like goog.Uri) and enums

  • :require for everything else

Import a class

This is only for when you would like to refer directly to a class which is also a namespace, otherwise just use :require in your ns form or use the require REPL helper.

(ns example.core
  (:import goog.Uri))
;; in REPL
(import 'goog.Uri)
(Uri. "http://example.com")
;;=> #<http://example.com>

Import an enum

(ns example.core
  (:import [goog.events EventType]))
;; in REPL
(import '[goog.events EventType])
EventType.CLICK
;;=> "click"

Requiring a function

(ns example.core
  (:require [goog.math :as math]))
;; in REPL
(require '[goog.math :as math])
(math/clamp -1 0 5)
;;=> 0

Sometimes symbols are not auto-included when requiring their parent namespace. This happens when those symbols are in their own file and require specific inclusion

(ns example.core
  (:require
    [goog.string :as gstring]
    goog.string.format))
;; in REPL
(require '[goog.string :as gstring])
(require 'goog.string.format)

(goog.string.format "%05d" 123)
;;=> 00123

;; or use the alias
(gstring/format "%05d" 123)
;;=> 00123

Searching for Examples

You can look for cljs files on Github that use goog.dom with the following search:

Or you can search Google Closure Library on Github for keywords pertaining to a function it might have: