Question

The following code prints NoMethodError. I don’t understand the reason . Though the method i am calling is private but i am calling it from within the class.Can’t a class var access it’s private variable/function ?. I could do this in Java.

class Tester
 private
   def func_pri
     puts("From a private function")
   end

 protected 
  def func_prot
    puts("From a protected function")
  end

 public
  def func_pub
     puts("From a public function")
  end

 public
  def caller(object)
    object.func_pub
    object.func_pri # This statement causes error
    object.func_prot
  end
 end

 o = Tester.new
 o.caller(o)

Answer 1

You cannot call private methods on an object, not even on self. Remove the object. part, then the call will go on self.

If you do want to call a private method, you can always use object.send(:func_pri).

Ruby is quite different than languages like Java in these terms. For more information, you might want to take a look at http://www.ruby-doc.org/docs/ProgrammingRuby/, chapter ‘Classes, Objects, and Variables’, section ‘Access Control’