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Comment by Jasper_ | Hacker News Reader

Yeah, `call` got supplanted by `bind`, and `bind` got supplanted by arrow functions. `apply` got supplanted by spread parameter syntax.

I've used them before for doing stupid reflection hacks (literally just used them today to build a debug UI where I can make sliders out of objects), but it's not code I would really want to ship in production.

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For the benefit of anyone who doesn't have a lot of experience with call, bind and arrow functions ()=>{}. No, these don't supplant one another and are separately useful in various ways. Reading the linked articles shows some of the related situations.

No. Bind creates a new function, call and apply do not.

More specifically, bind creates a new function + context, that you can hold a reference to and reuse, but you cannot do this with call or apply.

In practice though, many places that used apply/call tend to bind instead.

apply and call invoke a function with a specified receiver object, and arguments.

bind creates a new function that is bound to a specified receiver.

One of the most common places front-end devs encountered call/apply was when binding functions to event handlers. In those cases an anonymous function was often generated which used apply or call. Bind replaces this dance for many cases. Hence, most cases where devs encountered js call/apply were replaced by bind. There are differences between the two, but they largely didn't matter for most cases.

Unless you have strict performance requirements, then it does matter.

I got to use bind for a class based event handler, using arrows would bind this to the wrong context.. but maybe I'm doing it wrong.

I've used this syntax which auto-binds this, worked for me

  class Thing {
    method1 = () => {}
    method2 = () => {
      something.addEventListener('click', this.method1);
    }
  }

Fun trick. A bit tangled though

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