fill() not supported in IE11

Question

I have the following syntax. I am new to ES6 syntax.

const renderLoading = () => Array(20).fill(\'\').map(() => );

Answer 1

And this is a TypeScript compliant variant:

if (!Array.prototype.fill) {
    Object.defineProperty(Array.prototype, 'fill', {
        value: function(value) {

            if (this == null) {
                throw new TypeError('this is null or not defined');
            }

            const O = Object(this);
            // tslint:disable-next-line:no-bitwise
            const len = O.length >>> 0;
            const start = arguments[1];
            // tslint:disable-next-line:no-bitwise
            const relativeStart = start >> 0;

            let k = relativeStart < 0 ?
                Math.max(len + relativeStart, 0) :
                Math.min(relativeStart, len);

            const end = arguments[2];
            // tslint:disable-next-line:no-bitwise
            const relativeEnd = end === undefined ? len : end >> 0;

            const final = relativeEnd < 0 ?
                Math.max(len + relativeEnd, 0) :
                Math.min(relativeEnd, len);

            while (k < final) {
                O[k] = value;
                k++;
            }

            return O;
        }
    });
}