/*
 *  Main authors:
 *     Grégoire Dooms <dooms@info.ucl.ac.be>
 *
 *  Copyright:
 *     Grégoire Dooms (Université catholique de Louvain), 2005
 *
 *  Last modified:
 *     $Date: 2005-11-29 10:57:21 +0100 (Tue, 29 Nov 2005) $
 *     $Revision: 271 $
 *
 *  This file is part of CP(Graph)
 *
 *  See the file "contribs/graph/LICENSE" for information on usage and
 *  redistribution of this file, and for a
 *     DISCLAIMER OF ALL WARRANTIES.
 *
 */




namespace Gecode { namespace Graph {


  /**
   * \defgroup TaskActorGraphMEPC Graph modification events and propagation conditions
   * \ingroup TaskActorSet
   */

  //@{

  /// Domain operation has resulted in failure
  const ModEvent ME_GRAPH_FAILED = ME_GEN_FAILED;
  /// Domain operation has not changed domain
  const ModEvent ME_GRAPH_NONE  = ME_GEN_NONE;
  /// Domain operation has resulted in a value (assigned variable)
  const ModEvent ME_GRAPH_VAL   = ME_GEN_ASSIGNED;

  /**
   * \brief Domain operation has changed the least upper bound 
   *
   * Note that this implies that the domain has not resulted in a value
   * and that also neither cardinality nor the greatest lower bound
   * have changed.
   */
  const ModEvent ME_GRAPH_LUB  = ME_GRAPH_VAL + 1;
  /**
   * \brief Domain operation has changed the greatest lower bound
   *
   * Note that this implies that the domain has not resulted in a value
   * and that also neither cardinality nor the least upper bound
   * have changed.
   */
  const ModEvent ME_GRAPH_GLB   = ME_GRAPH_LUB + 1;
  /**
   * \brief Domain operation has changed both greatest lower and least
   * upper bound
   *
   * Note that this implies that the domain has not resulted in a value
   * and that also the cardinality has not changed.
   */
  const ModEvent ME_GRAPH_BB    = ME_GRAPH_GLB + 1;



  /**
   * \brief Propagate when a view becomes assigned (single value)
   *
   * If a propagator \a p depends on a view \a x with propagation
   * condition PC_GRAPH_VAL, then \a p is propagated when a domain
   * update operation on \a x returns the modification event ME_GRAPH_VAL.
   */
  const PropCond PC_GRAPH_VAL  = PC_GEN_ASSIGNED;
  /**
   * \brief Propagate when the greatest lower bound of a view changes
   *
   * If a propagator \a p depends on a view \a x with propagation
   * condition PC_GRAPH_GLB, then \a p is propagated when a domain
   * update operation on \a x returns the modification event ME_GRAPH_VAL or 
   * ME_GRAPH_GLB.
   */
  const PropCond PC_GRAPH_GLB  = PC_GRAPH_VAL + 1;
  /**
   * \brief Propagate when the least upper bound of a view changes
   *
   * If a propagator \a p depends on a view \a x with propagation
   * condition PC_GRAPH_LUB, then \a p is propagated when a domain
   * update operation on \a x returns the modification event ME_GRAPH_VAL or
   * ME_GRAPH_LUB.
   */
  const PropCond PC_GRAPH_LUB  = PC_GRAPH_GLB + 1;
  /**
   * \brief Propagate when any bound of a view changes
   *
   * If a propagator \a p depends on a view \a x with propagation
   * condition PC_GRAPH_ANY, then \a p is propagated when a domain
   * update operation on \a x returns any modification event but ME_GRAPH_FAILED and
   * ME_GRAPH_NONE.
   */
  const PropCond PC_GRAPH_ANY = PC_GRAPH_LUB + 1;
  //@}
  } }

// STATISTICS: graph-var