michael@0: /* Don't crash. */
michael@0: function foo(y) {
michael@0:   var x = y;
michael@0:   if (x != x)
michael@0:     return true;
michael@0:   return false;
michael@0: }
michael@0: assertEq(foo("three"), false);
michael@0: assertEq(foo(NaN), true);