public FingerTree <T, M> ToTree()
{
return(Match(one => _mk.Single(one.V),
two => _mk.Deep(_mk.One(two.V1), new Empty <Node <T, M>, M>(_m.Node), _mk.One(two.V2)),
three => _mk.Deep(_mk.Two(three.V1, three.V2), new Empty <Node <T, M>, M>(_m.Node), _mk.One(three.V3)),
four =>
_mk.Deep(_mk.Two(four.V1, four.V2), new Empty <Node <T, M>, M>(_m.Node), _mk.Two(four.V3, four.V4))));
}
public override FingerTree <T, M> AddLeft(T a)
{
return(_mk.Deep(_mk.One(a), new Empty <Node <T, M>, M>(Measured.Node), _mk.One(_item)));
}
public override Split <T, FingerTree <T, M>, M> Split(MeasurePredicate <M> predicate, M acc)
{
var mk = new MakeTree <Node <T, M>, M>(Measured.Node);
M prefixSize = Measured.Append(acc, _prefix.Size);
if (predicate(prefixSize))
{
Split <T, Digit <T, M>, M> split = _prefix.Split(predicate, acc);
FingerTree <T, M> leftTree = split.Left == null?_mk.Empty() : split.Left.ToTree();
FingerTree <T, M> rightTree;
if (split.Right != null)
{
rightTree = _mk.Deep(split.Right, _middle, _suffix);
}
else
{
rightTree = _middle.Match(e => _suffix.ToTree(),
s => _mk.Deep(s.Item.Match <Digit <T, M> >(x2 => _mk.Two(x2.V1, x2.V2),
x3 => _mk.Three(x3.V1, x3.V2, x3.V3)),
mk.Empty(), _suffix),
d =>
{
var leftView = _middle.Left;
return(_mk.Deep(leftView.Head.Match <Digit <T, M> >(x2 => _mk.Two(x2.V1, x2.V2),
x3 => _mk.Three(x3.V1, x3.V2, x3.V3)),
leftView.Tail, _suffix));
});
}
return(new Split <T, FingerTree <T, M>, M>(leftTree, split.Item, rightTree));
}
M middleSize = Measured.Append(prefixSize, _middle.Size);
if (predicate(middleSize))
{
Split <Node <T, M>, FingerTree <Node <T, M>, M>, M> split = _middle.Split(predicate, prefixSize);
Split <T, Digit <T, M>, M> splitMidLeft = split.Item
.Match <Digit <T, M> >(x2 => _mk.Two(x2.V1, x2.V2), x3 => _mk.Three(x3.V1, x3.V2, x3.V3))
.Split(predicate, Measured.Append(prefixSize, split.Left.Size));
FingerTree <T, M> leftTree = _mk.Deep(_prefix, split.Left, splitMidLeft.Left);
FingerTree <T, M> rightTree = _mk.Deep(splitMidLeft.Right, split.Right, _suffix);
return(new Split <T, FingerTree <T, M>, M>(leftTree, splitMidLeft.Item, rightTree));
}
Split <T, Digit <T, M>, M> splitSuffix = _suffix.Split(predicate, middleSize);
FingerTree <T, M> right = splitSuffix.Right == null?_mk.Empty() : splitSuffix.Right.ToTree();
FingerTree <T, M> left;
if (splitSuffix.Left != null)
{
left = _mk.Deep(_prefix, _middle, splitSuffix.Left);
}
else
{
left = _middle.Match(e => _prefix.ToTree(),
s => _mk.Deep(_prefix, mk.Empty(), s.Item.Match <Digit <T, M> >(x2 => _mk.Two(x2.V1, x2.V2),
x3 => _mk.Three(x3.V1, x3.V2, x3.V3))),
d =>
{
var rightView = _middle.Right;
return(_mk.Deep(_prefix, rightView.Tail, rightView.Head.Match <Digit <T, M> >(x2 => _mk.Two(x2.V1, x2.V2),
x3 => _mk.Three(x3.V1, x3.V2, x3.V3))));
});
}
return(new Split <T, FingerTree <T, M>, M>(left, splitSuffix.Item, right));
}