fancy

https://github.com/bakkdoor/fancy

The Fancy Programming Language Fancy is a fully self-hosted, dynamic, pure class-based object-oriented programming language heavily inspired by Smalltalk, Ruby and Erlang. It supports dynamic code evaluation (as in Ruby & Smalltalk), class-based mixins, generic pattern matching, runtime introspection & reflection, "monkey patching" and much more. It runs on Rubinius, the Ruby VM, and thus has first-class integration with Ruby's core library and any additional Ruby libraries that run on Rubinius, including most C-extensions.