visitTextSpan method

bool visitTextSpan (bool visitor(TextSpan span))

Walks this text span and its descendants in pre-order and calls visitor for each span that has text.

Implementation 

bool visitTextSpan(bool visitor(TextSpan span)) {
  if (text != null) {
    if (!visitor(this))
      return false;
  }
  if (children != null) {
    for (TextSpan child in children) {
      if (!child.visitTextSpan(visitor))
        return false;
    }
  }
  return true;
}