Background
Lisp is a programming language that’s been on my radar for a while, but I’ve never investigated until now. While browsing the web last night, I came across this Paul Graham article about the start of Viaweb and my curiousity was piqued.
This post is my attempt to consolidate my experience of getting a lisp development environment set up in July 2018.
For the rest of this post, [~] $ is my terminal prompt, and
* is the sbcl Common Lisp interpreter prompt
Lisp
SBCL (Steel Bank Common Lisp) appears to be the popular option for Common Lisp which, in turn, is the most popular open source Lisp dialect. This can be installed using homebrew:
$ brew install sbcl
To verify a Common Lisp interpreter is installed properly, open a terminal and
type sbcl to enter the Common Lisp
REPL:
[~] $ sbcl --noinform
* (+ 1 2 3)
6
* (quit)
[~] $
Editor
To my dismay, it seems as though the lisp programming environment is fundamentally tied to Emacs, an editor I’ve always eschewed. I can’t even close Emacs without Ctrl-C. Visual Studio Code is my preferred tool.
I installed a GUI version of GNU Emacs from Emacsforosx using homebrew:
[~] $ brew cask install emacs
Once brew finishes, this can be launched from the /Applications folder, using spotlight, or from the terminal with
[~] $ open -a /Applications/Emacs.app
Editor package manager
Some searching led to MELPA as the Emacs package manager I would have success with getting Slime - the Emacs Lisp helper package - installed.
I set up MELPA by following the installation instructions here:
[~] $ vi ~/.emacs
I pasted the MELPA initialization code below:
(require 'package)
(let* ((no-ssl (and (memq system-type '(windows-nt ms-dos))
(not (gnutls-available-p))))
(proto (if no-ssl "http" "https")))
;; Comment/uncomment these two lines to enable/disable MELPA and MELPA Stable as desired
(add-to-list 'package-archives (cons "melpa" (concat proto "://melpa.org/packages/")) t)
;;(add-to-list 'package-archives (cons "melpa-stable" (concat proto "://stable.melpa.org/packages/")) t)
(when (< emacs-major-version 24)
;; For important compatibility libraries like cl-lib
(add-to-list 'package-archives '("gnu" . (concat proto "://elpa.gnu.org/packages/")))))
(package-initialize)
Installing Slime
From the Slime Introduction:
SLIME is the “Superior Lisp Interaction Mode for Emacs.” SLIME extends Emacs with support for interactive programming in Common Lisp.
To install this, I restarted Emacs.app, and then ran the package manager to install Slime:
(within Emacs.app)
M-x package-install <return> slime <return>
I then added the Lisp interpreter I installed using Homebrew to my .emacs file:
(within iTerm.app)
[~] $ echo "(setq inferior-lisp-program \"/usr/local/bin/sbcl\")" >> ~/.emacs
Success
At this point, everything is set up and ready to run! Common Lisp programming
using SLIME can be initiated by opening Emacs.app and typing M-x slime <return>
Bonus round - Quicklisp
Quicklisp is the Common Lisp package
library manager. It can be installed by following the instructions at the
Quicklisp website:
Download Quicklisp.lisp:
[~] $ curl -O https://beta.quicklisp.org/quicklisp.lisp
Install Quicklisp and specify a specific path to install quicklisp to (I don’t want my home directory unnecessarily polluted, so I chose to install it to my :
[~] $ sbcl --noinform --load quicklisp.lisp
==== quicklisp quickstart 2015-01-28 loaded ====
To continue with installation, evaluate: (quicklisp-quickstart:install)
For installation options, evaluate: (quicklisp-quickstart:help)
* (quicklisp-quickstart:install :path "~/.quicklisp")
...<snip>...
==== quicklisp installed ====
To load a system, use: (ql:quickload "system-name")
To find systems, use: (ql:system-apropos "term")
To load Quicklisp every time you start Lisp, use: (ql:add-to-init-file)
For more information, see http://www.quicklisp.org/beta/
*
To force quicklisp to load at sbcl startup, execute the following post installation:
* (ql:add-to-init-file)
Verify that Quicklisp launches when the sbcl interperter starts by quitting
sbcl, relaunching it, and typing (ql:help):
[~] $ sbcl --noinform
* (ql:help)
"For help with Quicklisp, see http://www.quicklisp.org/beta/"
Verify that Emacs.app and the SLIME environment are correctly pulling in the
Quicklisp configuration by launching Emacs.app, running M-x slime <return>
and then entering:
* (ql:help)
"For help with Quicklisp, see http://www.quicklisp.org/beta/"
References
Paul Graham - Lisp Paul Graham - Beating the Averages Practical Common Lisp SLIME User Manual EmacsWiki - Emacs for MacOS Quicklisp
My .emacs file
After following the steps outlined above, this is what my .emacs file looks like (including two lines to change the meta key from alt/option to cmd on MacOS)
(require 'package)
(let* ((no-ssl (and (memq system-type '(windows-nt ms-dos))
(not (gnutls-available-p))))
(proto (if no-ssl "http" "https")))
;; Comment/uncomment these two lines to enable/disable MELPA and MELPA Stable as desired
(add-to-list 'package-archives (cons "melpa" (concat proto "://melpa.org/packages/")) t)
;;(add-to-list 'package-archives (cons "melpa-stable" (concat proto "://stable.melpa.org/packages/")) t)
(when (< emacs-major-version 24)
;; For important compatibility libraries like cl-lib
(add-to-list 'package-archives '("gnu" . (concat proto "://elpa.gnu.org/packages/")))))
(package-initialize)
(custom-set-variables
;; custom-set-variables was added by Custom.
;; If you edit it by hand, you could mess it up, so be careful.
;; Your init file should contain only one such instance.
;; If there is more than one, they won't work right.
'(package-selected-packages (quote (slime))))
(custom-set-faces
;; custom-set-faces was added by Custom.
;; If you edit it by hand, you could mess it up, so be careful.
;; Your init file should contain only one such instance.
;; If there is more than one, they won't work right.
)
(setq inferior-lisp-program "/usr/local/bin/sbcl")
(setq mac-option-modifier 'super)
(setq mac-command-modifier 'meta)