def in_scope?(name)
      ret = true if @callable.arguments_type.variable_index(name)
      ret = @callable.frame_type.variable_index(name) unless ret
      ret
    end
def in_scope?(name)
      ret = true if @callable.arguments_type.variable_index(name)
      ret = @callable.frame_type.variable_index(name) unless ret
      ret
    end
return true or false if the given name is in scope (arg/local)