export function xmlElementStartLines(text: string, pattern: RegExp): number[] {
  if (!pattern.global) throw new Error('Der XML-Zeilenmatcher muss global sein.');
  const masked = text.replace(/<!--[\s\S]*?-->/g, value => value.replace(/[^\r\n]/g, ' '));
  const lines: number[] = [];
  let cursor = 0;
  let line = 1;
  pattern.lastIndex = 0;
  for (const match of masked.matchAll(pattern)) {
    const matchIndex = match.index;
    if (matchIndex === undefined) continue;
    while (cursor < matchIndex) {
      if (masked.charCodeAt(cursor) === 13) {
        line += 1;
        cursor += masked.charCodeAt(cursor + 1) === 10 ? 2 : 1;
      } else if (masked.charCodeAt(cursor) === 10) {
        line += 1;
        cursor += 1;
      } else {
        cursor += 1;
      }
    }
    lines.push(line);
  }
  pattern.lastIndex = 0;
  return lines;
}