javascript-es6 | JavaScript ES6 Course https | Script Programming library

The correct syntax for an array union is:

Just a workaround (why Mirth cannot use JS template strings still unknown)

Still do not know why the template string is not working, but after playing with the Reference tab a bit and looking around the community forums found a workaround by dragging the Get Current Date reference into the Mapping field and specifying the desired format pattern as shown below.

After doing this and redeploying the channel, I see the date formatted in the way I was trying to do (though if anyone can explain why the template string evaluates to the literal code I'd mark that as the accepted answer because I still have seen no answer for why they don't actually work).

Are ES6 class private properties just syntactic sugar?

No. They're a fundamental addition to how objects work at an internal level. Private fields (as they're called) are held in new slots in the object that didn't exist before the proposal and are not accessible in other ways.

So I would like to understand if '#' syntax for private properties in ES6 classes is syntactic sugar and can be polyfilled in some way for function lovers like myself.

You can't use private properties without class syntax. (Future proposals may change that.) Instead, you'd have to keep doing what you're doing (the closure solution) or use a WeakMap only your functions have access to keyed by the object the properties relate to.

You've done your own closure examples, so here's your Person class using the WeakMap approach instead of private properties:

.then needs a callback, not a Promise - at the moment, you're calling createPromise(i) immediately, inside the loop. Create a function that, when called, returns a Promise instead:

You can accomplish this fairly easily without getting too fancy. Here's the algorithm:

1. Put the items from json1 into an object by id, so that you can look them up quickly.
2. For each item in json2: If it already exists, merge it with the existing item. Else, add it to objectsById.
3. Convert objectsById back to an array. I've used Object.values, but you can also do this easily with a loop.

Your guess is correct, it's happening because of bundler. Its a feature of bundler known as Dead code elimination. To know more about it, search for Tree Shaking or Dead code elimination.

If you are not going to use anything from imported module, source code of module will not be included in your build.

I think create-react-app use Webpack for bundling. If you want to disable the feature, starting the app in development mode may solve it. BTW, its good to remove unused code while building.

When a generator executes a yield statement

What I found is, the following can't use backtick

1. Object declaration

that make sense, you are passing the local object (Vehicle) to the parent class within constructor return super.proxify(this);.

Keep in mind the local Vehicle instance has not been instantiated yet (constructor block is not finished yet), so you cannot use this object in the mean time, you need to wait the constructor to done it's job.