function baseIndexOfWith(array, value, fromIndex, comparator) {
  var index = fromIndex - 1,
      length = array.length;

  while (++index < length) {
    if (comparator(array[index], value)) {
      return index;
    }
  }

  return -1;
}
This function is like `baseIndexOf` except that it accepts a comparator.

@private
@param {Array} array The array to inspect.
@param {*} value The value to search for.
@param {number} fromIndex The index to search from.
@param {Function} comparator The comparator invoked per element.
@returns {number} Returns the index of the matched value, else `-1`.