Burdock

Burdock is an Emacs minor mode for Ruby which provides structured editing and evaluation operations.

Requirements

Burdock requires the inf-ruby package.

Installation

Burdock is not available as an official package as of yet so it must be built from source.

From the command line execute the following or similar commands.

$ export BURDOCK_DIRECTORY=~/.emacs.d/lisp/burdock-mode
$ cd $BURDOCK_DIRECTORY
$ git clone https://github.com/noprompt/burdock-mode .
$ cd ruby
$ bundle install

Next, add the following source to your Emacs configuration wherever you deem appropriate. Then either evalaute it directly or restart Emacs.

(add-to-list 'load-path BURDOCK_DIRECTORY)
(require 'burdock-mode)

;; Tells burdock where the backend Ruby code lives. This can also be
;; configured with `M-x customize-group`.
(setq burdock-ruby-source-directory (concat BURDOCK_DIRECTORY "ruby/"))

;; Enable burdock-mode whenever ruby-mode is also enabled. This is
;; optional but recommended.
(add-hook 'ruby-mode-hook 'burdock-mode)

;; Whenever we initialize burdock-mode we should also start the
;; burdock process.
(add-hook 'burdock-mode-hook 'burdock-start)

BURDOCK_DIRECTORY here is a string which contains path to the root of the repository cloned in the first step.

At this point you should now be able to open a Ruby file and begin using the provided Burdock feature set.

Usage with inf-ruby-mode

One of the primary motivators for the creation of Burdock was the desired to have structured code evaluation experience complimentary to what is available in the lisp family of languages. Burdock enables this functionality by accurately extracting expressions from your Ruby buffer and sending them to the Ruby process created by inf-ruby-mode for evaluation. When applied judiciously this ability can promote a much faster feedback loop than the traditional write/run pattern commonly seen with Ruby development. It is a fantastic compliment to an automated test runner or other testing tool such as rspec-mode. Finally it is great way to poke at things.

To get an appreciation for this start a Ruby process by running M-x run-ruby or your preferred method then create a new Ruby buffer with the following code.

lambda do
  x = 1
  y = 2

  x + y
end.call

Now, position your cursor anywhere between the do and end delimiters and execute M-x burdock-evaluate-scope-at-point. With any luck you should see something similar to the following result in your Ruby REPL.

>> lambda do
?>   x = 1
>>   y = 2
>>   x + y
>> end.call
=> 3

Voilà!

The only thing left to do is bind this to something easier to type!