Skerrick

noun: skerrick
the smallest bit.
"there's not a skerrick of food in the house"

REPL-driven development for NodeJS

• Programming in tiny increments - Apply patches to your running program without having to restart it
• Tell me more!

Inspired by (check them out!):

• SLIME: The Superior Lisp Interaction Mode for Emacs
• CIDER: The Clojure(Script) Interactive Development Environment that Rocks!
• Calva: integrated REPL powered environment for enjoyable and productive Clojure and ClojureScript development in Visual Studio Code

⚠️ DISCLAIMERS ⚠️

• THIS PROJECT IS IN ALPHA STATE! I WOULD APPRECIATE IT IF YOU REPORT ANY BUGS/ISSUES YOU FIND. MAYBE EVEN CONTRIBUTE PATCHES/FIXES IF YOU HAVE THE TIME ;)
• The code is currently very messy and not well-written. I just wanted to get a working prototype out of the door as quickly as I could. I will be improving the implementation over time. Feel free to give me suggestions if you have any!

VSCode

✨ Documentation ✨

Emacs

Demos

Basic

Module support

Requirements

• node/npm installed and accessible by Emacs

Installation

skerrick is in MELPA

Or, if you're using Quelpa:

(quelpa '(skerrick :repo "anonimitoraf/skerrick" :fetcher github))

;; Needs to be run on the very first install of skerrick. Or when you want to upgrade.
(unless (equal (shell-command-to-string "type skerrick") "skerrick not found\n")
  (skerrick-install-or-upgrade-server-binary))

;; Should be run in a JS buffer; it is buffer specific.
;; (skerrick-start-server)

;; Now main function, entry point is:
;; M-x skerrick-eval-region

It may also be helpful to provide a quick keyboard shortcut. E.g., C-x C-e evaluates ELisp, so let's mimic that for JS buffers:

;; Evaluate a region, if any is selected; otherwise evaluate the current line.
(bind-key
 "C-x C-e"  (lambda ()
              (interactive)
              (if (use-region-p)
                  (skerrick-eval-region)
                (beginning-of-line)
                (set-mark-command nil)
                (end-of-line)
                (skerrick-eval-region)
                (pop-mark)))
 'js-mode-map)

Configuration

Configuration	Desc	Default
skerrick-server-port	Port to run the skerrick server on	4321
skerrick-result-overlay-face	Face used to display evaluation results
skerrick-result-overlay-char-count-trunc	Results with char count longer than this are truncated	120
skerrick-pop-result-buffer-for-stdout	Show result buffer if stdout is non-empty	t
skerrick-pop-result-buffer-for-stderr	Show result buffer if stderr is non-empty	t

Usage

Command	Desc
skerrick-install-or-upgrade-server-binary	Needs to be run on the very first install of skerrick. Or when you want to upgrade.
skerrick-start-server	Starts the server. Note that your current buffer will be evaluated, so you probably want to run this command while being on your program's entry point file.
skerrick-stop-server	Stops the server.
skerrick-eval-region	Evaluates the selected region. Shows the eval result as an overlay. Stdout/stderr get written to the buffer *skerrick-stdout-stderr*.

Write a plug-in for your editor/IDE!

• npm install -g skerrick - this installs the bin skerrick

  Invoked like so: skerrick PORT ENTRYPOINT_FULL_FILE_PATH

• The REST protocol is as simple as it can be:

  • POST to /eval payloads of shape:

      {
        "modulePath": "/full/path/to/file/of/code/to/eval",
        "code": "const x = 42; console.log(x); x + x;"
      }

  • Response shape:

      {
        "result": "84",
        "stdout": "42",
        "stderr": ""
      }

• 🚀 Tell me about your plug-in so I can add it to this README! 🚀