code: function indexOf(array, value, fromIndex) {
        var length = array == null ? 0 : array.length;
        if (!length) {
          return -1;
        }
        var index = fromIndex == null ? 0 : toInteger(fromIndex);
        if (index < 0) {
          index = nativeMax(length + index, 0);
        }
        return baseIndexOf(array, value, index);
      }
docs: Gets the index at which the first occurrence of `value` is found in `array`
  using [`SameValueZero`](http://ecma-international.org/ecma-262/7.0/#sec-samevaluezero)
  for equality comparisons. If `fromIndex` is negative, it's used as the
  offset from the end of `array`.
  
  @static
  @memberOf _
  @since 0.1.0
  @category Array
  @param {Array} array The array to inspect.
  @param {*} value The value to search for.
  @param {number} [fromIndex=0] The index to search from.
  @returns {number} Returns the index of the matched value, else `-1`.
  @example
  
  _.indexOf([1, 2, 1, 2], 2);
  // => 1
  
  // Search from the `fromIndex`.
  _.indexOf([1, 2, 1, 2], 2, 2);
  // => 3