Question

Did anyone set up something like this for himself using the existing
node.js REPL? I didn’t think of a quick way to do it.

The way I do it today is using emacs and this:
https://github.com/ivan4th/swank-js

This module is composed of:

1. A SLIME-js addon to emacs which, in combination with js2-mode, lets
   you simply issue a C-M-x somewhere in the body of a function def – and
   off goes the function’s string to the ..

2. Swank-js server (yes, you could eval from your local-machine
   directly to a remote process) written in Node.js – It receives the
   string of the function you eval’ed and actually evals it

3. A whole part that lets you connect to another port on that server
   with your BROWSER and then lets you manipulate the DOM on that browser
   (which is pretty amazing but not relevant)

My solution uses SLIME-js on the emacs side AND I require(‘swank-
js’) on my app.js file

Now.. I have several issues and questions regarding my solution or
other possible ones:

Q1: Is this overdoing it? Does someone have a secret way to eval stuff
from nano into his live process?

Q2: I had to change the way swank-js is EVALing.. it used some
kind of black magic like this:

var Script = process.binding('evals').Script;
var evalcx = Script.runInContext;
....
this.context = Script.createContext();
for (var i in global) this.context[i] = global[i];
this.context.module = module;
this.context.require = require;
...
r = evalcx("CODECODE", this.context, "repl");

which, as far I understand, just copies the global variables to the
new context, and upon eval, doesn’t change the original function
definitions – SOOO.. I am just using plain “eval” and IT
WORKS.

Do you have any comments regarding this?

Q3: In order to re-eval a function, it needs to be a GLOBAL function –
Is it bad practice to have all function definitions as global (clojure-like) ? Do you think there is another way to do this?

Answer 1

Actually, swank.js is getting much better, and it is now much easier to set up swank js with your project using NPM. I’m in the process of writing the documentation right now, but the functionality is there!