static int classSizeInBytes(Class c) ctex {
  L<File> files = cast get(getClassLoader(c), 'files);
  S name = c.getName() + ".class";
  for (File location : files) 
    if (location.isDirectory()) {
      File f = new File(location, name);
      if (f.exists()) ret toInt_checked(fileSize(f));
    } else if (location.isFile()) pcall {
      temp ZipFile zip = new ZipFile(location);
      ZipEntry entry = zip.getEntry(name);
      if (entry != null) ret toInt_checked(entry.getSize());
    }
  fail(name + " not found in: " + files);
}