michael@0: // for-of works with generators.
michael@0: 
michael@0: function range(n) {
michael@0:     for (var i = 0; i < n; i++)
michael@0:         yield i;
michael@0: }
michael@0: 
michael@0: var s = '';
michael@0: for (var a of range(4))
michael@0:     s += a;
michael@0: assertEq(s, '0123');