class Object # The hidden singleton lurks behind everyone def metaclass; class << self; self; end; end def meta_eval &blk; metaclass.instance_eval &blk; end # Adds methods to a metaclass def meta_def name, &blk meta_eval { define_method name, &blk } end # Defines an instance method within a class def class_def name, &blk class_eval { define_method name, &blk } end end