riversong-code-showcase/Source/Engine/Collections/IMultiDictionary.cs

using System.Collections.Generic;

namespace DanieleMarotta.RiversongCodeShowcase
{
    public interface IMultiDictionary<K, V, C> : IEnumerable<KeyValuePair<K, V>> where C : ICollection<V>
    {
        C this[K key] { get; }

        Dictionary<K, C>.KeyCollection Keys { get; }

        int KeyCount { get; }

        int ValueCount { get; }

        int Count(K key);

        bool Add(K key, V value);

        bool Remove(K key, V value);

        bool Remove(V value);

        void Clear(K key);

        void Clear();

        bool ContainsKey(K key);

        bool ContainsValue(K key, V value);

        bool ContainsValue(V value);

        bool TryGetValues(K key, out C values);
    }
}