Method propagate

gecode/set/element/union.hpp:108–336

  template<class View, class View0, class View1>
  ExecStatus
  ElementUnion<View,View0,View1>::propagate(Space& home, const ModEventDelta&) {
    Region r;
    int n = iv.size();

    bool loopVar;
    do {
      loopVar = false;

      // Cache the upper bound iterator, as we have to
      // modify the upper bound while iterating
      LubRanges<View0> x0ub(x0);
      Iter::Ranges::Cache x0ubc(r,x0ub);
      Iter::Ranges::ToValues<Iter::Ranges::Cache> vx0ub(x0ubc);

      GlbRanges<View0> x0lb(x0);
      Iter::Ranges::Cache x0lbc(r,x0lb);
      Iter::Ranges::ToValues<Iter::Ranges::Cache> vx0(x0lbc);

      // In the first iteration, compute in before[i] the union
      // of all the upper bounds of the x_i. At the same time,
      // exclude inconsistent x_i from x0 and remove them from
      // the list, cancel their dependencies.

      GLBndSet sofarBefore(home);
      LUBndSet selectedInter(home, IntSet (Limits::min,
                                   Limits::max));
      GLBndSet* before =
        static_cast<GLBndSet*>(r.ralloc(sizeof(GLBndSet)*n));

      int j = 0;
      int i = 0;

      unsigned int maxCard = 0;
      unsigned int minCard = Limits::card;

      while ( vx0ub() ) {

        // Remove vars at indices not in the upper bound
        if (iv[i].idx < vx0ub.val()) {
          iv[i].view.cancel(home,*this, PC_SET_ANY);
          ++i;
          continue;
        }
        assert(iv[i].idx == vx0ub.val());
        iv[j] = iv[i];

        View candidate = iv[j].view;
        int candidateInd = iv[j].idx;

        // inter = glb(candidate) & complement(lub(x1))
        GlbRanges<View> candlb(candidate);
        LubRanges<View1> x1ub(x1);
        Iter::Ranges::Diff<GlbRanges<View>, LubRanges<View1> >
          diff(candlb, x1ub);

        bool selectSingleInconsistent = false;
        if (x0.cardMax() <= 1) {