also a way to run code when object is deleted.
both of these are possibilities, not certainties.
R=rsc, iant
CC=golang-dev
https://golang.org/cl/181057
Variant types. A way to define a type as being the union of some set
of types.
<li>
+Possibly provide a method that will be run by the garbage
+collector when an item is freed.
+<li>
Generics. An active topic of discussion.
+<li>
+Exceptions. An active topic of discussion.
</ul>
<h3 id="Implementation_roadmap">