/b.js(6,21): error TS2339: Property 'x' does not exist on type 'B'.


==== /b.js (1 errors) ====
    class A { constructor() { this.x = 0; } }
    
    /** @augments A */
    class B {
        m() {
            return this.x;
                        ~
!!! error TS2339: Property 'x' does not exist on type 'B'.
        }
    }
    