michael@0: var obj;
michael@0: var counter = 0;
michael@0: var p = Proxy.create({
michael@0:     has : function(id) {
michael@0: 	if (id == 'xyz') {
michael@0: 	    ++counter;
michael@0: 	    if (counter == 7) {
michael@0: 		obj.__proto__ = null;
michael@0: 	    }
michael@0: 	    return true;
michael@0: 	}
michael@0: 	return false;
michael@0:     },
michael@0:     get : function(id) {
michael@0: 	if (id == 'xyz')
michael@0: 	    return 10;
michael@0:     }
michael@0: });
michael@0: 
michael@0: function test()
michael@0: {
michael@0:     Object.prototype.__proto__ = null;
michael@0:     obj = { xyz: 1};
michael@0:     var n = 0;
michael@0:     for (var i = 0; i != 100; ++i) {
michael@0: 	var s = obj.xyz;
michael@0: 	if (s)
michael@0: 	    ++n;
michael@0: 	if (i == 10) {
michael@0: 	    delete obj.xyz;
michael@0: 	    Object.prototype.__proto__ = p;
michael@0: 	}
michael@0: 
michael@0:     }
michael@0: }
michael@0: 
michael@0: try {
michael@0:     test();
michael@0: } catch (e) {}