// @strictNullChecks: true

var a1 = null;
var a2 = undefined;
var a3 = void 0;

var b1 = [];
var b2 = [,];
var b3 = [undefined];
var b4 = [[], []];
var b5 = [[], [,]];

declare function f<T>(x: T): T;

var c1 = f(null);
var c2 = f(undefined);
var c3 = f([]);