/// <summary>
/// This method is looking for a subset that contains values that
/// the outer set does not contain
/// </summary>
/// <param name="outerSet"></param>
/// <param name="space"></param>
/// <returns></returns>
public IPossible ReducedSetValues(IEnumerable <TKey> outerSet, ISpace <TKey> space)
{
Keys <TKey> oSet = new Keys <TKey>(outerSet);
oSet.ExceptWith(this);
IPossible reducedValues = space.AllValuesAt(this);
// Get all values in subset combination
foreach (TKey keyInner in this)
{
Possible innerValues = new Possible(space[keyInner]);
foreach (TKey keyOuter in oSet)
{
innerValues.FilterOut(space[keyOuter]);
}
// Each innerKey must have an exclusive value not in the outer set
if (innerValues.Count > 0)
{
reducedValues.IntersectPossible(innerValues);
}
else
{
reducedValues.Clear();
break;
}
}
return(reducedValues);
}