_createBaseFor.js

/**
 * Creates a base function for methods like `_.forIn` and `_.forOwn`.
 *
 * @private
 * @param {boolean} [fromRight] Specify iterating from right to left.
 * @returns {Function} Returns the new base function.
 */
function createBaseFor(fromRight) {
  return function(object, iteratee, keysFunc) {
    var index = -1,
        iterable = Object(object),
        props = keysFunc(object),
        length = props.length;

    while (length--) {
      var key = props[fromRight ? length : ++index];
      if (iteratee(iterable[key], key, iterable) === false) {
        break;
      }
    }
    return object;
  };
}

module.exports = createBaseFor;