public VersionedList <T> Add(T item)
{
return(new VersionedList <T>(
Items.Add(item),
Version + 1,
Changes.Add(ListChange.Added(Version, Items.Count, item))));
}
public VersionedList <T> Insert(int index, T item)
{
return(new VersionedList <T>(
Items.Insert(index, item),
Version + 1,
Changes.Add(ListChange.Added(Version, index, item))));
}
public VersionedList <T> SetItem(int index, T newItem)
{
var oldItem = Items[index];
return(new VersionedList <T>(
Items.SetItem(index, newItem),
Version + 1,
Changes.Add(ListChange.Replaced(Version, index, oldItem, newItem))
));
}
public VersionedList <T> Reverse(int index, int count)
{
var start = index;
var finish = index + count - 1;
var moves = Enumerable.Range(0, count)
.Select(i => ListChange.Moved(Version + i, start, finish - i, Items[start + i]));
return(new VersionedList <T>(Items.Reverse(index, count), Version + count, Changes.AddRange(moves)));
}
public VersionedList <T> Replace(T oldValue, T newValue)
{
var index = Items.IndexOf(oldValue);
return(new VersionedList <T>(
Items.Replace(oldValue, newValue),
Version + 1,
Changes.Add(ListChange.Replaced(Version, index, oldValue, newValue))
));
}
public VersionedList <T> Replace(T oldValue, T newValue, IEqualityComparer <T> equalityComparer)
{
var index = Items.IndexOf(oldValue, equalityComparer);
return(new VersionedList <T>(
Items.Replace(oldValue, newValue, equalityComparer),
Version + 1,
Changes.Add(ListChange.Replaced(Version, index, oldValue, newValue))
));
}
public VersionedList <T> AddRange(IEnumerable <T> items)
{
var itemsToAdd = items.ToArray();
var changes = Enumerable.Range(0, itemsToAdd.Length)
.Select(i => ListChange.Added(Version + i, Items.Count + i, itemsToAdd[i]));
return(new VersionedList <T>(
Items.AddRange(items),
Version + itemsToAdd.Length,
Changes.AddRange(changes)
));
}
private VersionedList <T> _removeWhere(Func <T, int, bool> predicate)
{
var pairs = Items
.Select((T item, int i) => new { Index = i, Item = item })
.ToArray();
var pairsToRemove = pairs
.Where(pair => predicate(pair.Item, pair.Index))
.OrderByDescending(pair => pair.Index)
.ToArray();
var remaining = pairs
.Where(pair => !predicate(pair.Item, pair.Index))
.Select(pair => pair.Item);
var changes = Enumerable.Range(0, pairsToRemove.Length)
.Select(i => ListChange.Removed(Version + i, pairsToRemove[i].Index, pairsToRemove[i].Item));
return(new VersionedList <T>(
ImmutableList.CreateRange(remaining),
Version + pairsToRemove.Length,
Changes.AddRange(changes)
));
}
private VersionedList(ImmutableList <T> items, int version)
: this(items, version, ImmutableList <IListChange <T> > .Empty)
{
Changes = Changes.Add(ListChange.Reset(Version - 1, Items));
}