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- var baseIteratee = require('./_baseIteratee'),
- createInverter = require('./_createInverter');
-
- /** Used for built-in method references. */
- var objectProto = Object.prototype;
-
- /** Used to check objects for own properties. */
- var hasOwnProperty = objectProto.hasOwnProperty;
-
- /**
- * Used to resolve the
- * [`toStringTag`](http://ecma-international.org/ecma-262/7.0/#sec-object.prototype.tostring)
- * of values.
- */
- var nativeObjectToString = objectProto.toString;
-
- /**
- * This method is like `_.invert` except that the inverted object is generated
- * from the results of running each element of `object` thru `iteratee`. The
- * corresponding inverted value of each inverted key is an array of keys
- * responsible for generating the inverted value. The iteratee is invoked
- * with one argument: (value).
- *
- * @static
- * @memberOf _
- * @since 4.1.0
- * @category Object
- * @param {Object} object The object to invert.
- * @param {Function} [iteratee=_.identity] The iteratee invoked per element.
- * @returns {Object} Returns the new inverted object.
- * @example
- *
- * var object = { 'a': 1, 'b': 2, 'c': 1 };
- *
- * _.invertBy(object);
- * // => { '1': ['a', 'c'], '2': ['b'] }
- *
- * _.invertBy(object, function(value) {
- * return 'group' + value;
- * });
- * // => { 'group1': ['a', 'c'], 'group2': ['b'] }
- */
- var invertBy = createInverter(function(result, value, key) {
- if (value != null &&
- typeof value.toString != 'function') {
- value = nativeObjectToString.call(value);
- }
-
- if (hasOwnProperty.call(result, value)) {
- result[value].push(key);
- } else {
- result[value] = [key];
- }
- }, baseIteratee);
-
- module.exports = invertBy;
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