public ImmutableBidirectionalDictionary <TFirst, TSecond> Add(TFirst first, TSecond second)
=> new ImmutableBidirectionalDictionary <TFirst, TSecond> (
FirstToSecond.Add(first, second),
SecondToFirst.Add(second, first));
public bool TryGetSecond(TFirst first, out TSecond second) => FirstToSecond.TryGetValue(first, out second);
public ImmutableBidirectionalDictionary <TFirst, TSecond> WithComparers(
IEqualityComparer <TFirst> firstKeyComparer,
IEqualityComparer <TSecond> secondKeyComparer)
=> new ImmutableBidirectionalDictionary <TFirst, TSecond> (
FirstToSecond.WithComparers(firstKeyComparer, secondKeyComparer),
SecondToFirst.WithComparers(secondKeyComparer, firstKeyComparer));