docs: @CanIgnoreReturnValue // some processors won't return a useful result
    public static <T> T readLines(Readable readable, LineProcessor<T> processor) throws IOException {
      checkNotNull(readable);
      checkNotNull(processor);
  
      LineReader lineReader = new LineReader(readable);
      String line;
      while ((line = lineReader.readLine()) != null) {
        if (!processor.processLine(line)) {
          break;
        }
      }
      return processor.getResult();
    }