blob: 86dd8af97760abead892d84fb48115ff88e8135b [file] [log] [blame]
var baseMerge = require('../internal/baseMerge'),
createAssigner = require('../internal/createAssigner');
/**
* Recursively merges own enumerable properties of the source object(s), that
* don't resolve to `undefined` into the destination object. Subsequent sources
* overwrite property assignments of previous sources. If `customizer` is
* provided it's invoked to produce the merged values of the destination and
* source properties. If `customizer` returns `undefined` merging is handled
* by the method instead. The `customizer` is bound to `thisArg` and invoked
* with five arguments: (objectValue, sourceValue, key, object, source).
*
* @static
* @memberOf _
* @category Object
* @param {Object} object The destination object.
* @param {...Object} [sources] The source objects.
* @param {Function} [customizer] The function to customize assigned values.
* @param {*} [thisArg] The `this` binding of `customizer`.
* @returns {Object} Returns `object`.
* @example
*
* var users = {
* 'data': [{ 'user': 'barney' }, { 'user': 'fred' }]
* };
*
* var ages = {
* 'data': [{ 'age': 36 }, { 'age': 40 }]
* };
*
* _.merge(users, ages);
* // => { 'data': [{ 'user': 'barney', 'age': 36 }, { 'user': 'fred', 'age': 40 }] }
*
* // using a customizer callback
* var object = {
* 'fruits': ['apple'],
* 'vegetables': ['beet']
* };
*
* var other = {
* 'fruits': ['banana'],
* 'vegetables': ['carrot']
* };
*
* _.merge(object, other, function(a, b) {
* if (_.isArray(a)) {
* return a.concat(b);
* }
* });
* // => { 'fruits': ['apple', 'banana'], 'vegetables': ['beet', 'carrot'] }
*/
var merge = createAssigner(baseMerge);
module.exports = merge;