Function lineNo

static/editor.md/lib/codemirror/lib/codemirror.js:7572–7582

(line)

  // Given a line object, find its line number by walking up through
  // its parent links.
  function lineNo(line) {
    if (line.parent == null) return null;
    var cur = line.parent, no = indexOf(cur.lines, line);
    for (var chunk = cur.parent; chunk; cur = chunk, chunk = chunk.parent) {
      for (var i = 0;; ++i) {
        if (chunk.children[i] == cur) break;
        no += chunk.children[i].chunkSize();
      }
    }
    return no + cur.first;
  }

  // Find the line at the given vertical position, using the height
  // information in the document tree.