created() {} vs created: function() {}

Question

I've seen some people use

created: function() {
  // code
}

and also

created () {
  // code
}

and then a warning in the Vue docs to not do this

created: () => {
  // code
}

I understand that the first one is the usual way of writing functions, and the last one is the new es6 arrow functions which bind the 'this' keyword to scope. But what is the middle one? It looks like a mix of both. What're the implications of using that?

Middle one is probably from a javascript class https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Classes — charlietfl, Dec 10 '17 at 07:19
Are you sure there's not a `function` before the second one, as in `function created () { // code }`? As written, it's invalid syntax unless it's in a class (h/t @charlietfl, who pointed this out first). — elixenide, Dec 10 '17 at 07:20
@EdCottrell It's also valid in an object literal (like the first and third examples would be) — Bergi, Dec 10 '17 at 11:51

Suren Srapyan · Accepted Answer · 2017-12-10T07:26:00.140

1

The first and the second are identical. The second one just is a ES6 syntax to defining function in the object.

const obj1 = {
  name: 'Obj1',
  create() {
    console.log(this.name);
  }
};

const obj2 = {
  name: 'Obj2',
  create: function() {
    console.log(this.name);
  }
};

obj1.create();
obj2.create();

edited Dec 10 '17 at 07:26

answered Dec 10 '17 at 07:22

Suren Srapyan

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that isn't es5 compatible – charlietfl Dec 10 '17 at 07:23
yes... to be honest i knew you could do that in new classes...didn't know it worked in object literals too – charlietfl Dec 10 '17 at 07:24
@charlietfl ES6 introduces a couple of useless syntactic sugars indeed (in my humble opinion). – Dec 10 '17 at 07:34
@WaldemarIce I know this is hard to admit, but ES6 was not necessary :-P – Dec 10 '17 at 13:17

created() {} vs created: function() {}

1 Answers1