The upcoming version of Cat supports scoped definitions, namespaces,
and type annotations. These are features I simply can't live without
in a programming language, and I view as crucial for a language to be
appropriate for actual software development.
I've written more about the type annotation system for Cat, and
provided some samples, at
http://www.artima.com/weblogs/viewpost.jsp?thread=168661
Christopher Diggins