code: function parseFileName(str) {
    const modMatch = str.match(/^(\d+).js$/);
    if (modMatch != null) {
      return {segmentId: 0, localId: Number(modMatch[1])};
    }
    const segMatch = str.match(/^seg-(\d+)(?:_(\d+))?.js$/);
    if (segMatch != null) {
      return {
        segmentId: Number(segMatch[1]),
        localId: segMatch[2] && Number(segMatch[2]),
      };
    }
    return UNKNOWN_MODULE_IDS;
  }
docs: /*
  If the file name of a stack frame is numeric (+ ".js"), we assume it's a
  lazily injected module coming from a "random access bundle". We are using
  special source maps for these bundles, so that we can symbolicate stack
  traces for multiple injected files with a single source map.
  
  There is also a convention for callsites that are in split segments of a
  bundle, named either `seg-3.js` for segment #3 for example, or `seg-3_5.js`
  for module #5 of segment #3 of a segmented RAM bundle.