ns

You must currently use the ns form only with the following caveats * You must use the :only form of :use * :require supports :as, :refer, and :rename - all options can be skipped - in this case a symbol can be used as a libspec directly - that is, (:require lib.foo) and (:require [lib.foo]) are both supported and mean the same thing - :rename specifies a map from referred var names to different symbols (and can be used to prevent clashes) - prefix lists are not supported * The only options for :refer-clojure are :exclude and :rename * :import is available for importing Google Closure classes - ClojureScript types and records should be brought in with :use or :require :refer, not :import ed * Macros must be defined in a different compilation stage than the one from where they are consumed. One way to achieve this is to define them in one namespace and use them from another. They are referenced via the :require-macros / :use-macros options to ns - :require-macros and :use-macros support the same forms that :require and :use do Implicit macro loading: If a namespace is required or used, and that namespace itself requires or uses macros from its own namespace, then the macros will be implicitly required or used using the same specifications. Furthermore, in this case, macro vars may be included in a :refer or :only spec. This oftentimes leads to simplified library usage, such that the consuming namespace need not be concerned about explicitly distinguishing between whether certain vars are functions or macros. For example: (ns testme.core (:require [cljs.test :as test :refer [test-var deftest]])) will result in test/is resolving properly, along with the test-var function and the deftest macro being available unqualified. Inline macro specification: As a convenience, :require can be given either :include-macros true or :refer-macros [syms...]. Both desugar into forms which explicitly load the matching Clojure file containing macros. (This works independently of whether the namespace being required internally requires or uses its own macros.) For example: (ns testme.core (:require [foo.core :as foo :refer [foo-fn] :include-macros true] [woz.core :as woz :refer [woz-fn] :refer-macros [app jx]])) is sugar for (ns testme.core (:require [foo.core :as foo :refer [foo-fn]] [woz.core :as woz :refer [woz-fn]]) (:require-macros [foo.core :as foo] [woz.core :as woz :refer [app jx]])) Auto-aliasing clojure namespaces: If a non-existing clojure.* namespace is required or used and a matching cljs.* namespace exists, the cljs.* namespace will be loaded and an alias will be automatically established from the clojure.* namespace to the cljs.* namespace. For example: (ns testme.core (:require [clojure.test])) will be automatically converted to (ns testme.core (:require [cljs.test :as clojure.test]))