TypeScript Version: 2.0.0

Code

// In lib.es2015.collection
interface MapConstructor {
    new (): Map<any, any>;
    // ...
}

Map, Set, WeakMap and WeakSet have unsafe constructor signatures. This leads to implicit unwanted behavior. They should be removed, in favor of their generic counterparts. Users who want unsafe code should use explicit casts, like this: new Map<any, any>()