Doc and source functions

The doc & source functions

If you are not using a Clojure aware editor or spend a lot of time in the REPL you can also view the documentation of a function by calling the doc function and see the source by calling the source function.

To use the doc & source functions in the REPL you should be in the user namespace.

Note On the command line, start a REPL with the command lein repl and then view the documentation for three common functions used in clojure

Make sure you are in the user namespace before calling the doc function. If you are in another namespace, either change back using (ns 'user) or see the next section on using these functions in another namespace.

(doc doc)
(doc map)
(doc filter)
(doc cons)

(source doc)
(source map)

Here is the doc string for doc

Here is the source code for the source function

Hint As the documentation for a function is part of its definition, by looking at the source of a function you also get the documentation.

Using doc & source function from another namespace

The doc and source functions are only included in the user namespace. If you switch to another namespace or your editor places you in the current namespace of your project, these functions will not be available unless you including core.repl in the current namespace.

From the REPL, evaluate the expression:

(use 'clojure.repl)

You could also require the clojure.repl library in your own code, however if you have a good editor it should provide these features without including this library. Therefore the following code is shown only as an example and not a recommended approach.

(ns foobar
(:require [clojure.repl :refer :all]))