1  var baseAssignValue = require('./_baseAssignValue'),
 2      eq = require('./eq');
 3  
 4  /** Used for built-in method references. */
 5  var objectProto = Object.prototype;
 6  
 7  /** Used to check objects for own properties. */
 8  var hasOwnProperty = objectProto.hasOwnProperty;
 9  
10  /**
11   * Assigns `value` to `key` of `object` if the existing value is not equivalent
12   * using [`SameValueZero`](http://ecma-international.org/ecma-262/7.0/#sec-samevaluezero)
13   * for equality comparisons.
14   *
15   * @private
16   * @param {Object} object The object to modify.
17   * @param {string} key The key of the property to assign.
18   * @param {*} value The value to assign.
19   */
20  function assignValue(object, key, value) {
21    var objValue = object[key];
22    if (!(hasOwnProperty.call(object, key) && eq(objValue, value)) ||
23        (value === undefined && !(key in object))) {
24      baseAssignValue(object, key, value);
25    }
26  }
27  
28  module.exports = assignValue;