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Accessing a private constant from a module

Is there a way to access a private constant from an included module?

This is what I would like to do:

module B
  def access_private_here
    puts MY_CONST
  end
end

class A
  include B
  private
    MY_CONST = 1
end

I know that if this constant were public I could do self.class::MY_CONST

, is there some way with closed minuses?

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2 answers


I would suggest writing it such that you don't have to change anything except include B

if you rename B

:



module B
  def access_private_here
    puts self.class::MY_CONST
  end
end

class A
  include B
  private
    MY_CONST = "cat"
end

A.new.access_private_here #=> "cat"
+2


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If you want to refer to it from another module:

module B
  def access_private_here
    puts A::MY_CONST
  end
end

If you want to declare it as a private constant, which is very unusual, you need to do this:



module A
  MY_CONST = 1
  private_constant :MY_CONST
end

It is closed at this point so you cannot link to it. As a side note, this kind of thing is best used using methods, not constants.

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