ResultRowImpl currentRow() {
int selectorCount = selectors.size();
Tree[] trees = new Tree[selectorCount];
for (int i = 0; i < selectorCount; i++) {
SelectorImpl s = selectors.get(i);
trees[i] = s.currentTree();
}
int columnCount = columns.length;
PropertyValue[] values = new PropertyValue[columnCount];
for (int i = 0; i < columnCount; i++) {
ColumnImpl c = columns[i];