Conkeror and Emacs are my two most used applications, one for web browsing and one for text editing, developing. It would be very great if I could use Emacs to interact directly with Conkeror for developing purpose. Fortunately, I found Mozrepl, an extension that “lets us program Firefox and other Mozilla-based applications from the inside” (quoted from Mozrepl homepage). This article is to summarize the steps on to set up Mozrepl in Conkeror and Emacs.

Install Mozrepl extension for Conkeror

You cannot directly install Mozrepl for Conkeror from Mozilla Add-ons page. Instead, you need to download it from the Mozilla Add-ons page, edit the install.rdf file and do a forced-installation following the instruction here Conkeror Extensions.

Config Mozrepl

Create a file named mozrepl-conkeror.js inside your home directory. Place this code as the file’s content

var conkeror = Cc["@conkeror.mozdev.org/application;1"]
	.getService().wrappedJSObject;

this.enter(conkeror);

Next, open your .conkerorrc and add this piece of code inside it to start the Mozrepl immediately when Conkeror start and then load the config file above.

user_pref('extensions.mozrepl.autoStart', true);
let (mozrepl_init = get_home_directory()) {
  mozrepl_init.appendRelativePath("mozrepl-conkeror.js");
  session_pref('extensions.mozrepl.initUrl', make_uri(mozrepl_init).spec);
}

Restart Conkeror and Mozrepl server is now ready for running.

Emacs integration

Extract the .xpi file you’ve downloaded before and copy moz.el file to somewhere in your Emacs’ load-path. Alternatively, you can download moz.el from here.

Add this to your .emacs

(autoload 'moz-minor-mode "moz" "Mozilla Minor and Inferior Mozilla Modes" t)

(add-hook 'javascript-mode-hook 'javascript-custom-setup)
(defun javascript-custom-setup ()
  (moz-minor-mode 1))

Restart Emacs for the code to take effect. Now in every javascript file, press C-c C-s to open the Mozrepl buffer. Enter the code there and press Return to evaluate it in Conkeror. For other key bindings, see here https://github.com/bard/mozrepl/wiki/Emacs-integration.