Ruby module instance variables

module_instance_var.rb

module SomeModule
  module_function
  def some_value; @some_value end
  def some_value= v; @some_value = v end
end

SomeModule.some_value
# => nil
SomeModule.some_value = 1
SomeModule.some_value
# => 1

The instance variable @some_value belongs to module SomeModule which is an object instance of the Module class.

SomeModule.class
# => Module

SomeModule.instance_variables
# => [:@some_value]