csharp

public readonly struct TypedEntityId<TTag> : IEquatable<TypedEntityId<TTag>>
{
    public EntityId Value { get; }

    private TypedEntityId(EntityId value)
    {
        Value = value;
    }

    public static implicit operator EntityId(TypedEntityId<TTag> typed) => typed.Value;
    public static explicit operator TypedEntityId<TTag>(EntityId entityId) => new TypedEntityId<TTag>(entityId);

    public bool Equals(TypedEntityId<TTag> other) => Value.Equals(other.Value);
    public override bool Equals(object obj) => obj is TypedEntityId<TTag> other && Equals(other);
    public override int GetHashCode() => Value.GetHashCode();
    public override string ToString() => Value.ToString();
}

public struct PlayerId : TypedEntityId<IPlayerIdTag>
{
    public PlayerId(EntityId entityId) : base(entityId) {}
    public static PlayerId Create(ulong value) => new PlayerId(EntityId.Create(EntityKindCore.Player, value));
}