Calling super from a class method

Question

When redefining a class method I want to be able to call super, just as I would in a instance method.

For example, I have a class hi with a class method

Hi.hi

class Hi

  def self.hi

    puts "hi"

  end

end



Hi.hi #=> "hi"

Now, Lets say i want to redefine

self.hi

class Hi

  def self.hi

    super

    puts "Oh!"

  end

end



Hi.hi #=> NoMethodError: super: no superclass method `hi' for Hi:Class

Why doesn't this work?

I know I can get the same functionality using alias (as below), it just seems rather unnecessary.

class Hi

  class << self

    def new_hi

      old_hi

      puts "Oh!"

    end

    alias :old_hi :hi

    alias :hi :new_hi 

  end

end



Hi.hi #=> "hi\n Oh!"

Is there a better way to do this?

Answer 1

Super works for child classes inherited from a parent class.

In your case alias is the only way. Or you can use alias_method:

alias_method :old_hi, :hi

def self.hi
  old_hi
  puts "Oh!"
end

Calling super from a class method

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