[eyelidlessness]

Using a class has some JIT optimization benefits if you always construct a value of the same shape.

Accessors: https://devblogs.microsoft.com/typescript/announcing-typescr...

[MrJohz]

That's true of objects too, as long as they have the same shape (which Typescript naturally helps with!). As long as the optimising compiler can see that your objects all have the same shape, and that you're always using the same properties, you're golden.

I hadn't noticed the accessors thing before, but it looks like that's an ECMAScript/TC39 thing, I guess to support the decorator implementation. Thanks for the link!