/// <summary>
/// Grounds the conditions by the specified substitution.
/// </summary>
/// <param name="conditions">Conditions.</param>
/// <param name="substitution">Variable substitution.</param>
/// <returns>Grounded conditions.</returns>
public Conditions Ground(Conditions conditions, ISubstitution substitution)
{
// (partially) ground the whole conditions by the specified substitution
Conditions newConditions = conditions.CloneEmpty();
foreach (var expression in conditions)
{
newConditions.Add(ExpressionsGrounder.Value.Ground(expression, substitution));
}
// for partially lifted conditions - remove parameters that were grounded by the substitution
if (conditions.Parameters != null)
{
newConditions.Parameters.Clear();
foreach (var parameter in conditions.Parameters)
{
if (!substitution.Contains(parameter.ParameterNameId))
{
newConditions.Parameters.Add(parameter.Clone());
}
}
// if the conditions are fully grounded, set the parameters as null
if (newConditions.Parameters.Count == 0)
{
newConditions.Parameters = null;
}
}
return(newConditions);
}
/// <summary>
/// Removes rigid relations from the specified conditions.
/// </summary>
/// <param name="conditions">Conditions.</param>
/// <returns>Conditions without rigid relations.</returns>
private Conditions ClearRigidRelations(Conditions conditions)
{
Conditions newConditions = conditions.CloneEmpty();
foreach (var expression in conditions)
{
PredicateExpression predicate = expression as PredicateExpression;
if (predicate != null)
{
if (EvaluationManager.IsPredicateRigidRelation(predicate.PredicateAtom))
{
continue;
}
}
newConditions.Add(expression);
}
return(newConditions);
}