function writeBlockSequence(state, level, object, compact) {
  var _result = '',
      _tag    = state.tag,
      index,
      length;

  for (index = 0, length = object.length; index < length; index += 1) {
    // Write only valid elements.
    if (writeNode(state, level + 1, object[index], true, true)) {
      if (!compact || index !== 0) {
        _result += generateNextLine(state, level);
      }

      if (state.dump && CHAR_LINE_FEED === state.dump.charCodeAt(0)) {
        _result += '-';
      } else {
        _result += '- ';
      }

      _result += state.dump;
    }
  }

  state.tag = _tag;
  state.dump = _result || '[]'; // Empty sequence if no valid values.
}
Internal method that keeps a track of which error we have already added, to avoid circular recursion

@private
@param {Error} err
@param {Set<Error>} seen
@returns {string}