Ruby private methods

privacy_example_failing.rb

class PrivacyExample
  def some_public_method
    self.some_private_method
  end

  def some_private_method
    "o hai"
  end
  private :some_private_method
end

#> PrivacyExample.new.some_public_method
#NoMethodError: private method `some_private_method' called for #<PrivacyExample:0x007f98c48f4800>
#        from (irb):3:in `some_public_method'
#        from (irb):12
#        from /Users/tomstuart/.rvm/rubies/ruby-1.9.2-p320/bin/irb:16:in `<main>'

privacy_example_passing.rb

class PrivacyExample
  def some_public_method
    some_private_method
  end

  def some_private_method
    "o hai"
  end
  private :some_private_method
end

#> PrivacyExample.new.some_public_method
# => "o hai"  

privacy_example_setters.rb

#of course, setters are completely different...

class PrivacyExample
  def some_var=(some_val)
    @some_var = some_val
  end
  private :some_var=

  def some_public_method
    some_var = "foo"
    @some_var
  end
end

#1.9.2p320 :011 > PrivacyExample.new.some_public_method
# => nil 
#some_var in some_public_method shadows the setter, so @some_var is still nil.

class PrivacyExample
  def some_var=(some_val)
    @some_var = some_val
  end
  private :some_var=

  def some_public_method
    #should fail - calling a private method with explicit receiver.
    self.some_var = "foo"
    @some_var
  end
end

#1.9.2p320 :018 > PrivacyExample.new.some_public_method                                       
# => "foo" 

#wat.

it's ok guys i have a fix

class Module
  def private(*args)
    protected(*args)
  end
end

Although actually that's no good either, because protected allows you to call the method from any instance of the defining class (or, I think, any instance of an object that includes the defining module). Which is something additional to private. So yea.

lolruby.