//****************************************
/// <summary>
/// Adds an element to the collection
/// </summary>
/// <param name="item">The element to add</param>
/// <returns>True if the element was added, False if it was already in the set</returns>
/// <exception cref="ArgumentNullException">Item was null</exception>
public bool Add(T item)
{ //****************************************
int Key, Index;
T? Current;
//****************************************
if (item is null)
{
throw new ArgumentNullException(nameof(item), "Cannot add null to a Weak Hash Set");
}
Key = Comparer.GetHashCode(item);
Index = Array.BinarySearch <SetItem>(_Values, 0, _Size, new SetItem(Key));
// Is there a matching hash code?
if (Index >= 0)
{
// BinarySearch is not guaranteed to return the first matching value, so we may need to move back
while (Index > 0 && _Values[Index - 1].HashCode == Key)
{
Index--;
}
for (;;)
{
try
{
Current = (T?)_Values[Index].Item.Target;
// Do we match this item?
if (Current != null && Comparer.Equals(Current, item))
{
return(false); // Yes, so return False
}
}
catch (InvalidOperationException)
{
// The GCHandle was disposed
}
// Are we at the end of the list?
if (Index == _Size - 1)
{
break; // Yes, so we need to insert the new item at the end
}
// Is there another item with the same key?
if (_Values[Index + 1].HashCode != Key)
{
break; // Nope, so we can insert the new item at the current Index
}
// Yes, so loop back and check that
Index++;
}
Insert(Index, Key, item);
return(true);
}
// No matching item, insert at the nearest spot above
Insert(~Index, Key, item);
return(true);
}
public PriorityQueue()
{
list = new T[16];
Count = 0;
Comparer = System.Collections.Generic.Comparer <T> .Default;
}
bool InRange(T item)
{
return(Comparer.Compare(item, lower) >= 0 &&
Comparer.Compare(item, upper) <= 0);
}
