use_custom_matcher_or_delegate (Spec::Matchers::OperatorMatcher)

    # File lib/spec/matchers/operator_matcher.rb, line 24
          def self.use_custom_matcher_or_delegate(operator)
            define_method(operator) do |expected|
              if matcher = OperatorMatcher.get(@actual.class, operator)
                @actual.send(::Spec::Matchers.last_should, matcher.new(expected))
              else
                eval_match(@actual, operator, expected)
              end
            end
          end