srecord noeq TimeoutException(double timeoutSeconds,
  O function,
  Thread thread) extends RuntimeException {
  @Override
  public S getMessage() {
    ret "Timeout after " + iceil(timeoutSeconds) + "s by " + shorten_str(function);
  }
  
  StackTraceElement[] innerStackTrace() {
    ret thread.getStackTrace();
  }
  
  public cached Cause getCause() {
    ret new Cause;
  }
  
  class Cause > Throwable {
    *() {
      super("Still calculating", null, false, true);
      setStackTrace(innerStackTrace());
    }
  }
}

Began life as a copy of #1034249