var es6 = (
    Array.from !== undefined &&
    Array.of !== undefined &&

    Math.acosh !== undefined &&
    Math.hypot !== undefined &&
    Math.imul !== undefined &&

    Number.isInteger !== undefined &&
    Number.isNaN !== undefined &&
    Number.EPSILON !== undefined &&

    Object.assign !== undefined &&

    Promise !== undefined &&

    Proxy !== undefined &&

    Map !== undefined &&
    Set !== undefined &&
    WeakMap !== undefined &&
    WeakSet !== undefined &&
    Symbol !== undefined
);