def define_dynamic_queries(roles)
      dynamic_module = Module.new do
        roles.each do |role|
          ["#{role}?".to_sym, "is_#{role}?".to_sym].each do |method|
            define_method(method) { is? role }
          end
        end
      end
      include dynamic_module
    end
def define_dynamic_queries(roles)
      dynamic_module = Module.new do
        roles.each do |role|
          ["#{role}?".to_sym, "is_#{role}?".to_sym].each do |method|
            define_method(method) { is? role }
          end
        end
      end
      include dynamic_module
    end
Defines dynamic queries for :role
   #is_<:role>?
   #<:role>?

 Defines new methods which call #is?(:role)