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Discussion on: Rethinking JavaScript: The complete elimination and eradication of JavaScript's this.

zeddotes profile image
zeddotes

What is the purpose of trying to access this.event on the 5th line? If this.event was a value declared in the parent scope, the fat arrow would actually save you. The implication of using EventEmitter2 would be so that you can access arguments from the callback of the events.on method (ie. args passed inside the callback).

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joelnet profile image
JavaScript Joel Author

The code is correct. This is how their API is written. I need the this from the function inside the events.on method, not the parent scope.

It works the same way jQuery's this context works here:

$('p').on('click', function() {
  console.log($(this).text())
})

You can't write an arrow function for these.

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zeddotes profile image
zeddotes

Actually, jQuery calls the callback of the element's this passed into it via apply and call. Check it out: code.jquery.com/jquery-3.3.1.js

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benwick profile image
benwick

In jquerys events this is the same as event.delegateTarget: api.jquery.com/event.delegateTarget/

So you can use the arrow function to get access to the parent context and still access the element you have attached the listener to... Please don't stop using this just because you don't know how a lib works.

$('p').on('click', (evt) => {
  console.log($(evt.delegateTarget).text())
})
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