Flip-Flops is not supported

```


s = true
a = 3.times {true if (s = ! s) ... (s) }
p a

See:
http://redhanded.hobix.com/inspect/hopscotchingArraysWithFlipFlops.html
http://svn.codehaus.org/jruby/trunk/jruby/test/test_flip.rb
```

Original issue reported on code.google.com by `xue.yong...@gmail.com` on 6 Sep 2007 at 2:32
