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Lodash _.union


The Lodash _.union method is a powerful utility function that finds the unique values in two or more arrays. It creates an array of unique values, in order, from all given arrays.

The syntax for calling the _.union method is straightforward, and it takes two or more array arguments as parameters. Here's an example:

_.union([2], [1, 2]);
// => [2, 1]

In the example above, we're taking two arrays [2] and [1,2] and finding the union of both the arrays into a new array [2,1].

One of the key features of the _.union method is that it eliminates duplicates from the final array, returning only unique values. It also maintains the order of the arrays provided.

It's also worth noting that the _.union method can successfully handle arrays containing a mixture of data types, including numbers, strings, objects, and nested arrays.

Another useful feature of the _.union method is that you can use it to combine any number of arrays in a single call, which can save you time and reduce code complexity.

In summary, the _.union method is an essential Lodash utility function that allows developers to find unique values across multiple arrays. It's easy to use, handles multiple data types, and ensures that you get an array of unique values while maintaining the order of the input arrays.