lodash/_baseNth.js

define(['./_isIndex'], function(isIndex) {

  /** Used as a safe reference for `undefined` in pre-ES5 environments. */
  var undefined;

  /**
   * The base implementation of `_.nth` which doesn't coerce arguments.
   *
   * @private
   * @param {Array} array The array to query.
   * @param {number} n The index of the element to return.
   * @returns {*} Returns the nth element of `array`.
   */
  function baseNth(array, n) {
    var length = array.length;
    if (!length) {
      return;
    }
    n += n < 0 ? length : 0;
    return isIndex(n, length) ? array[n] : undefined;
  }

  return baseNth;
});