Miskatonic University Press

Emacs refactoring

emacs

I spent a while updating my Emacs configuration, and this time nothing went wrong! I’m pleased with the refreshed and refactored setup. Everything looks the same as it did before, except for some colours in the dark Solarized theme, because I’m using a different package for that. Behind the scenes it’s all a lot tidier.

The main change is that everything now depends on John Wiegley’s use-package.

;; If it's not installed, get it.
(unless (package-installed-p 'use-package)
  (package-refresh-contents)
  (package-install 'use-package))

(eval-when-compile
  (require 'use-package))

;; Make sure that if I want a package, it gets installed automatically.
(setq use-package-always-ensure t)
Screenshot of Emacs while I'm editing this post
Screenshot of Emacs while I'm editing this post

With that in place, for every package I want to use, I use use-package to magically get it, install it and configure it. An average example is this, for the Emacs mode to use RuboCop, the Ruby syntax checker that tells you, as you’re writing, when you’ve made a mistake in your Ruby script.

;; Rubocop for pointing out errors (https://github.com/bbatsov/rubocop)
(use-package rubocop
  :diminish rubocop-mode
  :config
  (add-hook 'ruby-mode-hook 'rubocop-mode)
  )

The diminish line keeps away some cruft that says “RuboCop mode is on,” which I don’t need reminding; and the add-hook makes it so that whenever the editor is in Ruby mode (i.e., editing a Ruby script) then rubocop-mode is turned on automatically.

I’m now caught up to where a lot of other people were years ago. Next: moving it all into one big Org file!

One thing worth noting is that I fixed some problems I was having where M-x package-autoremove kept removing packages I actually wanted. It turned out the problem was with the variable package-selected-packages, which was introduced in 25.1 and is defined in custom.el. It had a huge list of packages, many of which I don’t want any more, but some I do want weren’t in it. Just one of those things.

I fixed it by brute force. I deleted the line from custom.el, quit Emacs, restarted, and ran M-x package-autoremove. Emacs said, Do you really want to remove all the 57 packages you have installed? I said yes. They got wiped out. I quit again, restarted, and this time use-package installed everything I wanted, updated package-selected-packages, and now everything is working correctly.