Namespaces
Namespaces are organized and controlled access to vars. Creation and switching to new nampspace can be done with ns.
(ns foo.bar)Current namespace can be inspected as follows.
*ns*
;; -> #<Namespace foo.bar>Var definitions can be directly accessible or with fully qualified namespace.
(def hello "world")
;; -> #'foo.bar/hello
hello
;; -> "world"
foo.bar/hello
;; -> "world"Switching to another namespace, the symbol will no longer be resolved. Fully qualified namespace resolves the symbol.
(ns diff.namespace)
;; -> nil
hello
;; -> CompilerException java.lang.RuntimeException:
;; -> Unable to resolve symbol: hello in this contex
foo.bar/hello
;; -> "world"If load a namespace, require is used.
(require 'clojure.set)Another way to do the above is to alias it.
(ns lalaland)
;; -> nil
(require '[foo.bar :as fb])
;; -> nil
fb/hello
;; -> "world"It is common to see nested in ns.
(ns lalaland
(:require [foo.bar :as fb]))
fb/hello
;; -> "world"