This looks very similar to Lua's coroutines: http://www.lua.org/pil/9.html http://www.lua.org/pil/9.html (click through on a right-arrow on that page and the

This looks very similar to Lua's coroutines: http://www.lua.org/pil/9.html http://www.lua.org/pil/9.html (click through on a right-arrow on that page and the pages following it to get more details and see some examples)