text: function emitError(stream) {
    return function(err) {
      stream.emit('error', err);
    }
  }
  
  function bubbleError(topStream, childStreams) {
    var i, len, onError;
  
    onError = emitError(topStream);
  
    for (i = 0, len = childStreams.length; i < len; i++) {
      childStreams[i].on('error', onError);
    }
  }
  
  module.exports = {
    _emitError : emitError,
    bubble     : bubbleError
  };
  