Laravel 5 Collections: Adding Values to a Collection With union

The union method will add the $items value to a copy of the existing collection. If there are key collisions between the collection instance and the provided $items, the elements from the collection instance will be used instead.

The union method does not modify the collection instance it was invoked on; instead, it will return a copy of the original collection with the provided $items added to it.

#Signature

1public function union(
2    $items
3);

#Example Use

The following example demonstrates both the basic use of the union method as well as its behavior when it encounters conflicting keys:

 1$collection  = collect([
 2   'firstName' => 'Johnathon',
 3   'lastName'  => 'Koster',
 4   'age'       => 27
 5])->union([
 6  'firstName' => null,
 7   'lastName' => null,
 8   'age' => 18,
 9   'city' => 'Mayville'
10]);

After the above code has executed, the $collection collection instance would contain the following values:

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