2018-fumichan-thesis / practice / vendor / bundle / ruby / 2.5.0 / gems / backports-3.11.4 / lib / backports / 1.9.1 / kernel / define_singleton_method.rb

unless Kernel.method_defined? :define_singleton_method
  module Kernel
    def define_singleton_method(*args, &block)
      class << self
        self
      end.send(:define_method, *args, &block)
    end
  end
end