Comment by Sébastien Portebois on "I have searched just about the entire internet for this so I am coming to you with a tough one. How do you spawn a node shell with a custom module pre loaded into it."

Hello there!

I'm not sure I got the question right, but I think I understood the main parts, and hopefully what follows should help you getting started. The main part is the REPL API from NodeJs.

In the sample below, I'll create 2 dumb modules in which I define custom functions, then I write some repl bootstrap to customize the way the interactive NodejS (its repl) is launched, and we'll see my modules are loaded automatically:

Let's start with the modules we want to load:

moduleA.js

'use strict';
exports.echo = (a) => console.log(`echo from A ${a}`);

moduleB.js

'use strict';
exports.add = (a, b) => a + b;

Then the magic happens here, in the bootstrap repl:

repl.js

const repl = require('repl').start({useGlobal: true});
for (let myModule of ['moduleA', 'moduleB']) {
    repl.context[myModule] = require(`./${myModule}`);
}

(To keep things simple all these files are in the same folder, but you're free to complexify this at will)

Now, rather than just typing $ node to enter the repl console, use that bootstrap script: $ node repl.js And now you're in the interactive shell, as usual, but moduleA and moduleB are alreayd loaded :

> moduleA.echo('test')
echo from A test

> moduleB.add(2, 3)
5

You can even add a #!/usr/env/bin node and do a chmod +x repl.js to call ./repl.js directly and enter your customized interactive shell.

I hope I understood your question correctly, Hope this helps, Séb

Well, Node can only load js, so you need to transpile your ts first (and make sure you don't use features that aren't yes supported by your Node version, or adjust your transpile options accordingly). But this is the only things required to get it working.

Let's start with the most basic TS config we could think of: tsconfig.json

{
    "compilerOptions": {
        "module": "commonjs",
        "target": "es6",
        "noImplicitAny": false,
        "sourceMap": false
    }
}

Now, let's write a simple TS class, in a file named moduleTS.ts

export class Offset {
    constructor(public qty:Number, public trend:'up'|'down' = 'up' ) {

    }

    public customLog() {
        console.log(`My output: qty:${this.qty}, trend:${this.trend}`);
    }
}

I kept is super simple, but we already have the default public members creation which is specific to TS (at least for now)

Don't forget to add that module to your repl pre-loading: (same script as before, with this one added)
repl.js

const repl = require('repl').start({useGlobal: true});
for (let myModule of ['moduleTS', 'moduleA', 'moduleB']) {
    repl.context[myModule] = require(`./${myModule}`);
}

Last step, don't forget to transpile your TS before to load the module (so that the up-to-date js export is loaded) tsc && node customRepl.js Obviously, if your ts code don'T change often, you don't have to transpile it every single time!

Now, in your Node console, you should be able to use the simple Offset class we created in Typescript:

// Inside Node console
> const tsOffset1 = new moduleTS.Offset(1.2)
undefined
> const tsOffset2 = new moduleTS.Offset(5, 'down')
undefined
> tsOffset1.customLog()
My output: qty:1.2, trend:up
undefined
> tsOffset2.customLog()
My output: qty:5, trend:down
undefined

Does this help?

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