--- singleton_method_undefined(name)

    ruby 1.7 feature

    ðۥ᥽åɤ Module#undef_method [Module/undef_method] ޤ 
    undef ˤ̤ˤ줿˥󥿥ץ꥿
    ƤӽФޤ
    name ˤ̤ˤ줿᥽å̾ Symbol Ϥޤ

        class Foo
          def singleton_method_undefined(name)
            puts "singleton method \"#{name}\" was undefined"
          end
        end

        obj = Foo.new
        def obj.foo
        end
        def obj.bar
        end

        class << obj
          undef_method :foo
        end
        obj.instance_eval {undef bar}

        => singleton method "foo" was undefined
           singleton method "bar" was undefined

    ̾Υ᥽åɤ̤Фեåˤ 
    Module#method_undefined [Module/method_undefined] Ȥޤ

