Ruby class initialize (constructor) is private method or public method?

Question

Is initialize method (constructor) private or public in ruby?

Answer 1

Let's see:

class Test
  def initialize; end
end

p Test.new.private_methods.sort.include?(:initialize)

This prints true, so initialize is a private method. This makes sense, it is only called by the new class method if the object is created. If we want, we can do something like this:

class Test
  def initialize
    @counter = 0
  end

  def reset!
    initialize
  end
end

Misusing the constructor like this could however lead to problems if it does more than simple variable initialization.

Answer 2

The initialize method in a class automatically becomes Private.

You can check it using:

puts ClassName.private_methods.sort