/// <summary>
/// See the <see cref="IImmutableDictionary{TKey, TValue}"/> interface.
/// </summary>
public ImmutableDictionary <TKey, TValue> WithComparers(IEqualityComparer <TKey>?keyComparer, IEqualityComparer <TValue>?valueComparer)
{
if (keyComparer == null)
{
keyComparer = EqualityComparer <TKey> .Default;
}
if (valueComparer == null)
{
valueComparer = EqualityComparer <TValue> .Default;
}
if (this.KeyComparer == keyComparer)
{
if (this.ValueComparer == valueComparer)
{
return(this);
}
else
{
// When the key comparer is the same but the value comparer is different, we don't need a whole new tree
// because the structure of the tree does not depend on the value comparer.
// We just need a new root node to store the new value comparer.
var comparers = _comparers.WithValueComparer(valueComparer);
return(new ImmutableDictionary <TKey, TValue>(_root, comparers, _count));
}
}
else
{
var comparers = Comparers.Get(keyComparer, valueComparer);
var set = new ImmutableDictionary <TKey, TValue>(comparers);
set = set.AddRange(this, avoidToHashMap: true);
return(set);
}
}