Can I invoke an instance method on a Ruby module without including it?

Question

Background:

I have a module which declares a number of instance methods

module UsefulThings
  def get_file; ...
  def delete_file; ...

  def forma         


        

Answer 1

A. In case you, always want to call them in a "qualified", standalone way (UsefulThings.get_file), then just make them static as others pointed out,

module UsefulThings
  def self.get_file; ...
  def self.delete_file; ...

  def self.format_text(x); ...

  # Or.. make all of the "static"
  class << self
     def write_file; ...
     def commit_file; ...
  end

end

B. If you still want to keep the mixin approach in same cases, as well the one-off standalone invocation, you can have a one-liner module that extends itself with the mixin:

module UsefulThingsMixin
  def get_file; ...
  def delete_file; ...

  def format_text(x); ...
end

module UsefulThings
  extend UsefulThingsMixin
end

So both works then:

  UsefulThings.get_file()       # one off

   class MyUser
      include UsefulThingsMixin  
      def f
         format_text             # all useful things available directly
      end
   end 

IMHO it's cleaner than module_function for every single method - in case want all of them.