I'm experimenting with Electron and I was trying to load an html file, and I store the path to that file in a private variable. Refer to code below.

However Path.join fails with this error:

BUT if I pass a string literal with the same value it works.

Non-working code:

import * as Electron from 'electron'
import * as Path from 'path'
import { Option, Some, None } from './option'

export default class Main
{
    private indexFilePath = 'index.html'
    private app: Electron.App
    private browserWindow: Option<Electron.BrowserWindow>

    constructor (app: Electron.App)
    {
        this.app = app
        this.browserWindow = new None()
        this.app.on('ready', this.onReady)
    }

    private onReady(): void
    {
        this.browserWindow = new Some(new Electron.BrowserWindow({
            width: 800,
            height: 600
        }))
        this.browserWindow.unwrap().loadFile(Path.join(__dirname, this.indexFilePath))
    }
}

Working code:

import * as Electron from 'electron'
import * as Path from 'path'
import { Option, Some, None } from './option'

export default class Main
{
    private app: Electron.App
    private browserWindow: Option<Electron.BrowserWindow>

    constructor (app: Electron.App)
    {
        this.app = app
        this.browserWindow = new None()
        this.app.on('ready', this.onReady)
    }

    private onReady(): void
    {
        this.browserWindow = new Some(new Electron.BrowserWindow({
            width: 800,
            height: 600
        }))
        this.browserWindow.unwrap().loadFile(Path.join(__dirname, 'index.html'))
    }
}

This doesn't make any sense to me and just increases my frustration with anything that has javascript in it. It feels like a whacky supersonic plane that could obliterate itself at any moment...

I did check if it was some weird typescript compilation error but no, doesn't matter which javascript version I choose the result is the same. Compiled code looks like this, I see nothing wrong with it either:

class Main {
    constructor(app) {
        this.indexFilePath = 'index.html';
        this.app = app;
        this.browserWindow = new option_1.None();
        this.app.on('ready', this.onReady);
    }
    onReady() {
        this.browserWindow = new option_1.Some(new Electron.BrowserWindow({
            width: 800,
            height: 600
        }));
        this.browserWindow.unwrap().loadFile(Path.join(__dirname, this.indexFilePath));
    }
}