Function baseFindKey

lodash.js:790–799

* The base implementation of methods like `_.findKey` and `_.findLastKey`, * without support for iteratee shorthands, which iterates over `collection` * using `eachFunc`. * * @private * @param {Array|Object} collection The collection to inspect. * @param {Function} predicate The fu

(collection, predicate, eachFunc)

   * @returns {*} Returns the found element or its key, else `undefined`.
   */
  function baseFindKey(collection, predicate, eachFunc) {
    var result;
    eachFunc(collection, function(value, key, collection) {
      if (predicate(value, key, collection)) {
        result = key;
        return false;
      }
    });
    return result;
  }

  /**
   * The base implementation of `_.findIndex` and `_.findLastIndex` without