lodash/internal/hashHas.js

define(['./nativeCreate'], function(nativeCreate) {

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

  /** Used for built-in method references. */
  var objectProto = Object.prototype;

  /** Used to check objects for own properties. */
  var hasOwnProperty = objectProto.hasOwnProperty;

  /**
   * Checks if a hash value for `key` exists.
   *
   * @private
   * @param {Object} hash The hash to query.
   * @param {string} key The key of the entry to check.
   * @returns {boolean} Returns `true` if an entry for `key` exists, else `false`.
   */
  function hashHas(hash, key) {
    return nativeCreate ? hash[key] !== undefined : hasOwnProperty.call(hash, key);
  }

  return hashHas;
});