Lodash union method
语法：
Creates an array of unique values, in order, from all given arrays using SameValueZero for equality comparisons.
参数
[arrays] (...Array) − The array to inspect.
输出：
(Array) − Returns the new array of combined values.
实例：
var _ = require('lodash');
var numbers = [1, 2, 3, 4]
var result = _.union(numbers, [2]);
console.log(result);
var result = _.union(numbers, [2, 5]);
console.log(result);
Save the above program in
tester.js. Run the following command to execute this program.
命令：
输出：
[ 1, 2, 3, 4 ]
[ 1, 2, 3, 4, 5 ]
