/// <summary>
/// Joins two Patricia Tries having different keys with common branch.
/// </summary>
/// <param name="prefixA">Prfix of the first Trie.</param>
/// <param name="nodeA">First Patricia Trie.</param>
/// <param name="prefixB">Prefix of the second Trie.</param>
/// <param name="nodeB">Second Trie.</param>
/// <returns>New Patritia Trie node having given nodes as her children.</returns>
public static IPatriciaNode <T> Join <T>(int prefixA, IPatriciaNode <T> nodeA, int prefixB, IPatriciaNode <T> nodeB)
{
var bb = BranchingBit(prefixA, prefixB);
var newPrefix = prefixA & (bb - 1);
return((prefixA & bb) == 0 ? new PatriciaBranch <T>(newPrefix, bb, nodeA, nodeB) : new PatriciaBranch <T>(newPrefix, bb, nodeB, nodeA));
}
private IPatriciaNode <T> CreateNode <T>(IEnumerable <T> items)
where T : class
{
IPatriciaNode <T> empty = EmptyPatriciaTrie <T> .Instance;
return(items.Aggregate(empty, (current, item) => current.Modify(item.GetHashCode(), InsertOperation(item))));
}
private ImmutableHashSet(IPatriciaNode <T> root)
{
if (root == null)
{
throw new ArgumentNullException(nameof(root));
}
_root = root;
}
public void RemovingSequentialKeys_Test()
{
var items = Enumerable.Range(0, _items.Length).
Zip(_items, (i, s) => new KeyValuePair <int, string>(i, s)).ToArray();
IPatriciaNode <string> empty = EmptyPatriciaTrie <string> .Instance;
var node = items.Aggregate(empty, (current, item) => current.Modify(item.Key, InsertOperation(item.Value)));
foreach (var item in items)
{
node = node.Modify(item.Key, NullOperation <string>()) ?? EmptyPatriciaTrie <string> .Instance;
CollectionAssert.DoesNotContain(node.GetItems(), item.Value);
}
}
// Constructors
public ImmutableHashSet()
{
_root = EmptyPatriciaTrie <T> .Instance;
}
public PatriciaBranch(int prefix, int mask, IPatriciaNode <T> left, IPatriciaNode <T> right)
: this(prefix, mask, new[] { left, right })
{
}
private ImmutableHashDictionary(IPatriciaNode <KeyValuePair <TKey, TValue> > root)
{
_root = root;
}
// Constructors
public ImmutableHashDictionary()
{
_root = EmptyPatriciaTrie <KeyValuePair <TKey, TValue> > .Instance;
}
