foo.js(12,16): error TS18048: 'b' is possibly 'undefined'.
foo.js(12,20): error TS18048: 'c' is possibly 'undefined'.


==== foo.js (2 errors) ====
    /**
     * foo
     *
     * @public
     * @param {object} opts
     * @param {number} opts.a
     * @param {number} [opts.b]
     * @param {number} [opts.c]
     * @returns {number}
     */
    function foo({ a, b, c }) {
        return a + b + c;
                   ~
!!! error TS18048: 'b' is possibly 'undefined'.
                       ~
!!! error TS18048: 'c' is possibly 'undefined'.
    }
    