text: function newReduce(array, callback, initialValue){
      let previousValue, i;
      if (arguments.length > 2){
          previousValue = initialValue;
          i = 0;
      }
      else {
          previousValue = array[0];
          i = 1;
      }
      for (i; i < array.length; i++){
          previousValue = callback(previousValue, array[i], i, array);
      }
      return previousValue;
  }
  module.exports = newReduce;