How to pass 'this' into a Promise without caching outside?

Question

I have a variable called LangDataService.isDataReady that is a Promise wawiting to be resolved. Upon resolve some logic will happen. How can I pass this into that Promise?

LangDataService.isDataReady.then(function () {
    this.modalOn()
});

I know i can cache var self_ = this; but I'm curious of other alternatives?

[Arrow function](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Functions/Arrow_functions) — Andreas, Jan 15 '16 at 20:23
I believe @Andreas is referring to the fact that `arrow functions` have a lexical-scoped `this`. — John Hascall, Jan 15 '16 at 20:25
@Andreas unfortunatlly arrow functions aren't widely supported and babel will just transpile to var this_ = this; — Armeen Moon, Jan 15 '16 at 20:26
You've asked for alternatives and this is one ;) [IE11 (and below), Safari and Konquerer](https://kangax.github.io/compat-table/es6/) are the only browser not supporting arrow functions. Chrome, Firefox and IE Edge do. Therefor I would disagree with the "widely" :) — Andreas, Jan 15 '16 at 20:31

score 33 · Accepted Answer · answered Jan 15 '16 at 20:25

33

LangDataService.isDataReady.then(function () {
  this.modalOn()
}.bind(this));

answered Jan 15 '16 at 20:25

matt3141

4,303
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2

Man I swear I tried that lol. I must have just put it in the wrong spot. – Armeen Moon Jan 15 '16 at 20:28
4

@MatthewHarwood likely you chained the `bind` call to `.then()`, not `function () {...}`. – Trent Jun 13 '18 at 17:52

How to pass 'this' into a Promise without caching outside?

1 Answers1