AnyRange r = index.toRange();
int size = name.size();
Any a = r.getLeft();
int start = a.isDefined() ? a.toInt() : 0;
a = r.getRight();
int end = a.isDefined() ? a.toInt() : size;
long l = ArrayUtils.adjust2(start, end, size);
start = (int)(l & 0xffffffff);
int length = (int)(l >> 32);
if (start == 0) {
return new AnyName(name.getPrefix(length));