private static void RecurGetStatesInternal <T>(IRegexFSMState <T> startState, HashSet <IRegexFSMState <T> > states)
{
if (states.Add(startState))
{
foreach (var transition in startState.Transitions.Where(transition => transition.Target != null))
{
RegexFSMUtility.RecurGetStatesInternal(transition.Target, states);
}
}
}
private static void RecurGetReachableTransitionsInternal <T>(IRegexFSMTransition <T> transition, HashSet <IRegexFSMTransition <T> > transitions)
{
foreach (var t in transition.Target.Transitions)
{
if (transitions.Add(t) && t is IEpsilonTransition)
{
RegexFSMUtility.RecurGetReachableTransitionsInternal(transition, transitions);
}
}
}
private static void RecurGetReachableStatesInternal <T>(IRegexFSMState <T> startState, HashSet <IRegexFSMState <T> > states)
{
foreach (var transition in startState.Transitions.Where(_transition => _transition != null && _transition.Target != null))
{
if (transition is IEpsilonTransition && states.Add(transition.Target))
{
RegexFSMUtility.RecurGetReachableStatesInternal(transition.Target, states);
}
}
}
/// <summary>
/// 递归获取指定转换开始能经到的所有转换的集合。
/// </summary>
/// <param name="transition">指定的转换。</param>
/// <returns>指定转换开始能经到的所有转换的集合。</returns>
/// <exception cref="ArgumentNullException"><paramref name="transition"/> 的值为 null 。</exception>
public static IEnumerable <IRegexFSMTransition <T> > RecurGetTransitions <T>(this IRegexFSMTransition <T> transition)
{
if (transition == null)
{
throw new ArgumentNullException(nameof(transition));
}
HashSet <IRegexFSMTransition <T> > transitions = new HashSet <IRegexFSMTransition <T> >();
RegexFSMUtility.RecurGetTransitionsInternal(transition, transitions);
return(transitions);
}
/// <summary>
/// 递归获取指定起始状态开始能达到的所有状态的集合。
/// </summary>
/// <param name="startState">指定的起始状态。</param>
/// <returns>指定起始状态开始能达到的所有状态的集合。</returns>
/// <exception cref="ArgumentNullException"><paramref name="startState"/> 的值为 null 。</exception>
public static IEnumerable <IRegexFSMState <T> > RecurGetStates <T>(this IRegexFSMState <T> startState)
{
if (startState == null)
{
throw new ArgumentNullException(nameof(startState));
}
HashSet <IRegexFSMState <T> > states = new HashSet <IRegexFSMState <T> >();
RegexFSMUtility.RecurGetStatesInternal(startState, states);
return(states);
}
private static void RecurGetTransitionsInternal <T>(IRegexFSMTransition <T> transition, HashSet <IRegexFSMTransition <T> > transitions)
{
if (transitions.Add(transition))
{
if (transition.Target != null)
{
foreach (var _transition in transition.Target.Transitions.Where(t => t != null))
{
RegexFSMUtility.RecurGetTransitionsInternal(_transition, transitions);
}
}
}
}
/// <summary>
/// 递归获取指定转换开始无须接受输入就能达到的所有状态的集合。
/// </summary>
/// <param name="transition">指定的转换。</param>
/// <returns>指定转换开始无须接受输入就能达到的所有状态的集合。</returns>
public static IEnumerable <IRegexFSMState <T> > RecurGetReachableStates <T>(this IRegexFSMTransition <T> transition)
{
if (transition == null)
{
throw new ArgumentNullException(nameof(transition));
}
HashSet <IRegexFSMState <T> > states = new HashSet <IRegexFSMState <T> > {
transition.Target
};
RegexFSMUtility.RecurGetReachableStatesInternal(transition.Target, states);
return(states);
}
