class SecretNumber def initialize @secret = rand(20) end def hint puts "The number is #{"not " if secret end private def secret @secret end end s = SecretNumber.new s.secret # NoMethodError: private method `secret' called for # # s.hint # The number is greater than 10. #--- class LessSecretNumber < SecretNumber def hint lower = secret-rand(10)-1 upper = secret+rand(10)+1 "The number is somewhere between #{lower} and #{upper}." end end ls = LessSecretNumber.new ls.hint # => "The number is somewhere between -3 and 16." ls.hint # => "The number is somewhere between -1 and 15." ls.hint # => "The number is somewhere between -2 and 16." #--- class MyClass def public_method1 end def public_method2 end protected def protected_method1 end private def private_method1 end def private_method2 end end #--- class LessSecretNumber def compare(other) if secret == other.secret comparison = "equal to" else comparison = secret > other.secret ? "greater than" : "less than" end "This secret number is #{comparison} the secret number you passed in." end end a = LessSecretNumber.new b = LessSecretNumber.new a.hint # => "The number is somewhere between 17 and 22." b.hint # => "The number is somewhere between 0 and 12." a.compare(b) # NoMethodError: private method `secret' called for # # #--- class SecretNumber protected :secret end a.compare(b) # => "This secret number is greater than the secret number you passed in." b.compare(a) # => "This secret number is less than the secret number you passed in." #--- class MethodWithManySecrets :private # This method will show up in the RDoc, even though it's private. def secret_method_1 end # This method will not show up in the RDoc. def secret_method_2 # :nodoc: end end #--- s.send(:secret) # => 19 #---
