Feature request: migration from callbacks towards asynchronous functions (await/async) in UI5-controllers

Issue: Asynchronous functions (await/async) have been introduced to ECMAScript/JavaScript back in June 2016, since then await/async became a best practise for a writing an asynchronous code in JS, allowing to avoid a callback hell.

Unfortunately, UI5 stayed away from the trend and even in 2020 a typical UI5-controller from the very beginning contains at least two nested callback and looks likes:

sap.ui.define([
	"sap/ui/core/mvc/Controller"
], function (Controller) {
	"use strict";

	return Controller.extend("ui5.tst.TST.controller.View1", {
		onInit: function () {
			/*…*/
		}
	});
});

Feature request: To make a «facelifting» to all UI5-controllers and to refactor the codebase, moving from multiple nested callbacks towards asynchronous functions (await/async), making code less nested and therefore easier-to-read.

[brelian]

Totally agree with @pubmikeb . ES6/7 brings many conveniences to developers. If there is a plan to support it, I believe there will be many developers willing to participate, including me.

[pubmikeb]

Yes, I realize the IE11-compatibility affects some modern standards adaptation. But what about providing two branches, let say, the modern and the legacy-one? For Chromium-based/Firefox browsers and for IE11 respectively. With an appropriate CI/CD infrastructure such task can be automated.

Anyway, the IE11 end-of-life is a matter of couple of next years, why not to let benefit from the modern standards out-of-box already today at least for those, who are not binded with the IE11 support?

P.S. Regardless the ES7 support, a TypeScript build of UI5 would be a prefect thing, especially due to its strong-typed nature.