Sure. That's why I made sure to say it'll give you 99% of what you want. Not 99% of immutable data structure capabilities :).
Though I'm sure folks may disagree with what I'm suggesting they "want" but I do not believe it's a good pattern to follow where a complex object needs to be immutable in JavaScript.
> JavaScript not enforcing immutability of nested objects with Object.freeze. So if you want to enforce that, you're going to have to call Object.freeze on every child object, which becomes a nightmare to write and maintain.
Which is why you should never ever do that. It's a bad pattern in a dynamic language to try and make complex structures completely immutable. It's best to simply find alternative ways of accessing them if you do not want to expose it to modification.
> While it is a little bit of a pain almost every framework and probably half of the libraries in existence on npm have a copy function.
The problem isn't just the usability of the copy operation (and even if it were, you still have the performance issue); there is also the problem of JavaScript not enforcing immutability of nested objects with Object.freeze. So if you want to enforce that, you're going to have to call Object.freeze on every child object, which becomes a nightmare to write and maintain.