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Ruby - File-Private Methods

In ruby, is there a way to define a method that each class sees in a file (or in a module), but not files that require a file?

Associated, but not quite the same: is it possible to override a method (for example, a method from a standard library class) so that this override is visible only in the current file? All other files should view the original definition.

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2 answers

No and no.

The only appearances in Ruby are public, protected, and private. There is no concept of file-level visibility. Perhaps you can "trick" and do something like this:

# In some file foobar.rb

class Foo
  def to_bar
    Bar.new.file_private
  end
end

class Bar
  def file_private
    raise unless caller[0].split(':')[0] == __FILE__
  end
end

# In IRB or some other file

Foo.new.to_bar  #=> nil
Bar.new.file_private  #=> RuntimeError

. . , .

, . . , public/protected/private. send , . - , , . , :P.

, , . - , , , , , , , .

+8

  • Object (, ). Object, , Foo .

    class Object
  @@file_only_methods = []

  def file_only(method_name)
    method_name = method_name.to_sym
    new_method_name = "file_only_#{method_name}".to_sym
    self.send(:alias_method, new_method_name, method_name)
    self.send(:undef_method, method_name)
    self.send(:private, new_method_name)
    @@file_only_methods << method_name
  end


  def method_missing(method_name, *arg, &block)
    if @@file_only_methods.include? method_name
      if __FILE__ == $0
        self.send("file_only_#{method_name}".to_sym,*arg,&block)
      else
        raise "Method #{method_name} is called outside the definition file."
      end
    else
      raise "Method #{method_name} does not exist."
    end
  end
end

class Foo
  def bar
    puts 'bar method'
  end
  file_only :bar
end

Foo.new.bar
#output:bar method
Foo.new.x
#output:no method

    2.rb,

    require_relative 'file1'
Foo.new.bar
#output: Method bar is called outside the definition file.
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