he predicate <TT>copyq depth = true</TT> will be copied and used for recomputation.
        As an example, a fixed distance recomputation policy can be defined using
        <TT>fun copyq d = d mod fixedDistance = 0</TT>, where <TT>fixedDistance</TT> is a given integer.
        Note that although this scheme is quite flexible, it is not possible to define real <I>adaptative</I>
        policies that way.
        </P>
    </DD>

    <DT>
      <TT><A name="mask">mask</A></TT>
    </DT>
    <DD><P>A debug mas