michael@0: function g() {}
michael@0: 
michael@0: function h() {
michael@0:     for (var i = 0; i < 9; i++)
michael@0: 	x.f = i;
michael@0: }
michael@0: 
michael@0: function j() {
michael@0:     x.f();
michael@0: }
michael@0: 
michael@0: var x = {f: 0.7, g: g};
michael@0: x.g();  // interpreter brands x
michael@0: h();
michael@0: print(shapeOf(x));
michael@0: x.f = function (){}; // does not change x's shape
michael@0: j();
michael@0: print(shapeOf(x));
michael@0: h(); // should change x's shape
michael@0: 
michael@0: var thrown = 'none';
michael@0: try {
michael@0:     j(); // should throw since x.f === 8
michael@0: } catch (exc) {
michael@0:     thrown = exc.name;
michael@0: }
michael@0: assertEq(thrown, 'TypeError');