/// <summary>
/// Returns an <see cref="IEnumerable{T}"/> of Dequeued Items from the Back of the
/// <paramref name="deque"/>. The returned items will be in
/// <see cref="Generic.IDeque{T}.DequeueBack"/> order and there may be as many as
/// up to <paramref name="count"/> items.
/// </summary>
/// <param name="deque"></param>
/// <param name="count"></param>
/// <returns></returns>
public static IEnumerable <object> DequeueBackMany(this IDeque deque, int count = 1)
{
while (count-- > 0 && deque.Count > 0)
{
yield return(deque.DequeueBack());
}
}
/// <summary>
/// Tries to Dequeue as Many <see cref="object"/> Items as possible. May return with
/// a <paramref name="result"/> that contains up to <paramref name="count"/> number of
/// them. The returned <paramref name="result"/> will be in
/// <see cref="Generic.IDeque{T}.DequeueBack"/> order.
/// </summary>
/// <param name="deque"></param>
/// <param name="result"></param>
/// <param name="count"></param>
/// <returns></returns>
public static bool TryDequeueBackMany(this IDeque deque, out IEnumerable <object> result, int count = 1)
{
result = new List <object>();
while (count-- > 0 && deque.Count > 0)
{
((IList <object>)result).Add(deque.DequeueBack());
}
return(result.Any());
}
public void DoUndo(IGraphProcessingEnvironment procEnv)
{
String attrName = _attrType.Name;
LGSPGraphProcessingEnvironment procEnv_ = (LGSPGraphProcessingEnvironment)procEnv;
if (_undoOperation == UndoOperation.PutElement)
{
if (_attrType.Kind == AttributeKind.SetAttr)
{
ChangingElementAttribute(procEnv_);
IDictionary dict = (IDictionary)_elem.GetAttribute(_attrType.Name);
dict.Add(_value, null);
}
else if (_attrType.Kind == AttributeKind.MapAttr)
{
ChangingElementAttribute(procEnv_);
IDictionary dict = (IDictionary)_elem.GetAttribute(_attrType.Name);
dict.Add(_keyOfValue, _value);
}
else if (_attrType.Kind == AttributeKind.ArrayAttr)
{
ChangingElementAttribute(procEnv_);
IList array = (IList)_elem.GetAttribute(_attrType.Name);
if (_keyOfValue == null)
{
array.Add(_value);
}
else
{
array.Insert((int)_keyOfValue, _value);
}
}
else //if(_attrType.Kind == AttributeKind.DequeAttr)
{
ChangingElementAttribute(procEnv_);
IDeque deque = (IDeque)_elem.GetAttribute(_attrType.Name);
if (_keyOfValue == null)
{
deque.EnqueueFront(_value);
}
else
{
deque.EnqueueAt((int)_keyOfValue, _value);
}
}
}
else if (_undoOperation == UndoOperation.RemoveElement)
{
if (_attrType.Kind == AttributeKind.SetAttr)
{
ChangingElementAttribute(procEnv_);
IDictionary dict = (IDictionary)_elem.GetAttribute(_attrType.Name);
dict.Remove(_value);
}
else if (_attrType.Kind == AttributeKind.MapAttr)
{
ChangingElementAttribute(procEnv_);
IDictionary dict = (IDictionary)_elem.GetAttribute(_attrType.Name);
dict.Remove(_keyOfValue);
}
else if (_attrType.Kind == AttributeKind.ArrayAttr)
{
ChangingElementAttribute(procEnv_);
IList array = (IList)_elem.GetAttribute(_attrType.Name);
if (_keyOfValue == null)
{
array.RemoveAt(array.Count - 1);
}
else
{
array.RemoveAt((int)_keyOfValue);
}
}
else //if(_attrType.Kind == AttributeKind.DequeAttr)
{
ChangingElementAttribute(procEnv_);
IDeque deque = (IDeque)_elem.GetAttribute(_attrType.Name);
if (_keyOfValue == null)
{
deque.DequeueBack();
}
else
{
deque.DequeueAt((int)_keyOfValue);
}
}
}
else if (_undoOperation == UndoOperation.AssignElement)
{
if (_attrType.Kind == AttributeKind.ArrayAttr)
{
ChangingElementAttribute(procEnv_);
IList array = (IList)_elem.GetAttribute(_attrType.Name);
array[(int)_keyOfValue] = _value;
}
else if (_attrType.Kind == AttributeKind.DequeAttr)
{
ChangingElementAttribute(procEnv_);
IDeque deque = (IDeque)_elem.GetAttribute(_attrType.Name);
deque[(int)_keyOfValue] = _value;
}
else //if(_attrType.Kind == AttributeKind.MapAttr)
{
ChangingElementAttribute(procEnv_);
IDictionary dict = (IDictionary)_elem.GetAttribute(_attrType.Name);
dict[_keyOfValue] = _value;
}
}
else if (_undoOperation == UndoOperation.Assign)
{
ChangingElementAttribute(procEnv_);
_elem.SetAttribute(attrName, _value);
}
// otherwise UndoOperation.None
}