// TODO: Stavet seznam setu.
/// <summary>
/// Adds the transition to the transition index if a transition equivalent to it is not there yet. If it is, it uses the already existing transition instead.
/// </summary>
/// <param name="transitionsByTargetState">The transition index (indexed by the target state).</param>
/// <param name="key">The target state.</param>
/// <param name="value">The new transition.</param>
/// <param name="comparer">The comparer.</param>
/// <returns>The new transition if it wasn't in the index yet, the existing tranwsition otherwise.</returns>
private ITransition AddTransitionOrGetExisting(Dictionary <State, HashSet <ITransition> > transitionsByTargetState, State key, ITransition value, TransitionNonrecursiveEqualityComparer comparer)
{
if (!transitionsByTargetState.ContainsKey(key))
{
transitionsByTargetState.Add(key, new HashSet <ITransition>(comparer)
{
value
});
return(value);
}
var set = transitionsByTargetState[key];
if (set.Contains(value))
{
return(set.Single(p => comparer.Equals(p, value)));
}
set.Add(value);
return(value);
}