class RSpec::Matchers::BuiltIn::StartAndEndWith

def matches?(actual)
  @actual = actual.respond_to?(:[]) ? actual : (raise ArgumentError.new("#{actual.inspect} does not respond to :[]"))
  begin
    @expected.respond_to?(:length) ? subset_matches?(@expected, @actual) : element_matches?(@expected, @actual)
  rescue ArgumentError
    raise ArgumentError.new("#{actual.inspect} does not have ordered elements")
  end
end