unionWith source npm

_.unionWith([arrays], [comparator])

This method is like _.union except that it accepts comparator which is invoked to compare elements of arrays. The comparator is invoked with two arguments: (arrVal, othVal).

Arguments

  1. [arrays] (...Array)

    The arrays to inspect.

  2. [comparator] (Function)

    The function invoked per element.

Returns (Array)

Returns the new array of combined values.

Example

var objects = [{ 'x': 1, 'y': 2 }, { 'x': 2, 'y': 1 }];
var others = [{ 'x': 1, 'y': 1 }, { 'x': 1, 'y': 2 }];

_.unionWith(objects, others, _.isEqual);
// => [{ 'x': 1, 'y': 2 }, { 'x': 2, 'y': 1 }, { 'x': 1, 'y': 1 }]