var(userId, itemId, count) = input;
get => getValue(ref userId, Constants.Unspecified);
// Add user's word pair transation (int, UserWordPair)[] userWords = ConvertToUserWordPairs(userId, pairsToAdd, inverted).ToArray();
var(userId, grpName) = (data.Value.Key, data.Value.Value);
var(userId, groupId, roleId) = (Guid.NewGuid(), Guid.NewGuid(), Guid.NewGuid());
foreach (var(userId, status) in updates)
await repository.RemovePermissionsFromUserAsync(userId, removedPermissions.ToList());