/// <summary>
/// Creates a rope from the specified input.
/// This operation runs in O(N).
/// </summary>
/// <exception cref="ArgumentNullException">input is null.</exception>
public Rope(IEnumerable <T> input)
{
if (input == null)
{
throw new ArgumentNullException("input");
}
var inputRope = input as Rope <T>;
if (inputRope != null)
{
// clone ropes instead of copying them
inputRope.root.Publish();
root = inputRope.root;
}
else
{
var text = input as string;
if (text != null)
{
// if a string is IEnumerable<T>, then T must be char
((Rope <char>)(object) this).root = CharRope.InitFromString(text);
}
else
{
var arr = ToArray(input);
root = RopeNode <T> .CreateFromArray(arr, 0, arr.Length);
}
}
root.CheckInvariants();
}
/// <summary>
/// Creates a rope from a part of the array.
/// This operation runs in O(N).
/// </summary>
/// <exception cref="ArgumentNullException">input is null.</exception>
public Rope(T[] array, int arrayIndex, int count)
{
VerifyArrayWithRange(array, arrayIndex, count);
root = RopeNode <T> .CreateFromArray(array, arrayIndex, count);
root.CheckInvariants();
}
internal void CheckInvariants()
{
if (height == 0)
{
Debug.Assert(left == null && right == null);
if (contents == null)
{
Debug.Assert(this is FunctionNode <T>);
Debug.Assert(length > 0);
Debug.Assert(isShared);
}
else
{
Debug.Assert(contents != null && contents.Length == NodeSize);
Debug.Assert(length >= 0 && length <= NodeSize);
}
}
else
{
Debug.Assert(left != null && right != null);
Debug.Assert(contents == null);
Debug.Assert(length == left.length + right.length);
Debug.Assert(height == 1 + Math.Max(left.height, right.height));
Debug.Assert(Math.Abs(Balance) <= 1);
// this is an additional invariant that forces the tree to combine small leafs to prevent excessive memory usage:
Debug.Assert(length > NodeSize);
// note that this invariant ensures that all nodes except for the empty rope's single node have at least length 1
if (isShared)
{
Debug.Assert(left.isShared && right.isShared);
}
left.CheckInvariants();
right.CheckInvariants();
}
}
/// <summary>
/// Creates a new rope representing the empty string.
/// </summary>
public Rope()
{
// we'll construct the empty rope as a clone of an imaginary static empty rope
root = RopeNode <T> .emptyRopeNode;
root.CheckInvariants();
}
internal Rope(RopeNode <T> root)
{
this.root = root;
root.CheckInvariants();
}