th]], return 1.
        1. If _isoDate1_.[[Month]] &lt; _isoDate2_.[[Month]], return -1.
        1. If _isoDate1_.[[Day]] > _isoDate2_.[[Day]], return 1.
        1. If _isoDate1_.[[Day]] &lt; _isoDate2_.[[Day]], return -1.
        1. Return 0.
      </emu-alg>
    </emu-clause>

    <emu-clause id="sec-temporal-differencetemporalplaindate" type="abstract operation">
      <h1>
        DifferenceTemporalPlainDate (
          _operation_: ~since~ or ~until~,
          _temporalDate_: a Temporal.PlainDate,
   