parse_comment_ex.ts

function parseComment(comment: string): string {
  const result: string[] = [];
  const parser = new Parser({
    ontext: text => result.push(replace(text)),
    onopentag: (tag, attrs) => {
      switch (tag) {
        case 'a': result.push(`{@link ${attrs['href']} `); break;
        case 'em': case 'i': result.push('_'); break;
        case 'strong': case 'b': reslt.push('__'); break;
        // ...
        default: throw new Error(`Unknown tag "${tag}".`);
      },
      onclosetag: tag => {
        case 'a': result.push('}'); break;
        case 'em': case 'i': result.push('_'); break;
        case 'strong': case 'b': reslt.push('__'); break;
        // ...
        default: throw new Error(`Unknown tag "${tag}".`);
      }
    }
  });
  parser.write(comment);
  parser.end();

  // ... turn result into 'lines'
  return lines.length === 1 ? `* lines[0] ` :
                              ('*\n *' + lines.join('\n *') + '\n ');
}