Why RLisp will not support Ruby class variables

RLisp tries to be as Ruby-like as it reasonable can. For example it supports Global::Constants, @instance_variables, $global_variables, and self. It does not support semantically ugly features like Constants_Without_Fully_Specified_Scope, public/private/protected distinction, and Perlish magic variables of $~, $1 and family, trying to use cleaner solutions instead.

I'm adding another to the list of officially not supported features - @@class_variables. They simply lack any sensible semantics. The following code:

class Foo
 @@xyzzy = 6
 def hello
   @@xyzzy
 end
end

class Bar < Foo
 @@xyzzy = 42
end

p Foo.new.hello
p Bar.new.hello
p Foo.new.instance_eval { @@xyzzy }

in Ruby 1.8 produces:

42
42
semantics_of_cvars.rb:16: uninitialized class variable @@xyzzy in Object (NameError)
      from semantics_of_cvars.rb:16:in `instance_eval'
      from semantics_of_cvars.rb:16

On the other hand in Ruby 1.9:

6
6
semantics_of_cvars.rb:16: warning: class variable access from toplevel singleton method
semantics_of_cvars.rb:16: uninitialized class variable @@xyzzy in Object (NameError)
      from semantics_of_cvars.rb:16

I don't remember ever using class variables, but I had a vague feeling @@xyzzy would mean something like self.class.class_variable_get(:@@xyzzy). Apparently the meaning is much uglier and frankly I cannot see any situation in which it could possibly be useful in Ruby and even less so in RLisp - unlike Ruby def, RLisp fn/defun/method/... do not wipe out surrounding context, so we can use plain local variables.

(class Object
(let xyzzy 42)
(method hello () (print xyzzy))
; xyzzy is a normal lexical variable visible until we exit class definition
)
; not visible any more
[self hello] # => 42