// @allowJs: true
// @checkJs: true
// @noEmit: true
// @lib: es2017

class MySet extends Set {
    constructor() {
        super();
    }
}

class MyWeakSet extends WeakSet {
    constructor() {
        super();
    }
}

class MyMap extends Map {
    constructor() {
        super();
    }
}

class MyWeakMap extends WeakMap {
    constructor() {
        super();
    }
}