michael@0: // 'this' is lexically scoped in arrow functions
michael@0: 
michael@0: var obj = {
michael@0:     f: function (expected) {
michael@0:         assertEq(this, expected);
michael@0:         return a => this;
michael@0:     }
michael@0: };
michael@0: 
michael@0: var g = obj.f(obj);
michael@0: assertEq(g(), obj);
michael@0: 
michael@0: var obj2 = {f: obj.f};
michael@0: var g2 = obj2.f(obj2);
michael@0: assertEq(g2(), obj2);
michael@0: assertEq(g(), obj);
michael@0: