 ?>

  <DL>
    <DT>
      <TT>type item</TT>
    </DT>
    <DD>
      <P>The type of elements in the set.</P>
    </DD>

    <DT>
      <TT>type set</TT> <BR>
      <TT>type t = set</TT>
    </DT>
    <DD>
      <P>The type of sets over elements of type <TT>item</TT>.</P>
    </DD>

    <DT>
      <TT>exception Unknown of item</TT>
    </DT>
    <DD>
      <P>Indicates that an item could not be found in the set.</P>
    </DD>

    <DT>
      <TT>exception Collision of item</TT>
    </DT>
    <DD>
      <P>