How to properly merge multiple collections in Laravel

Question

I want to merge multiple collections into one. I do have a solution, which is the following:

$allItems = $collection1->merge($collection2)                         ->merge($collection3)                         ->merge($collection4)                         ->merge($collection5); 

This actually does work, but I run into problems in cases where some or all of the collections contain no objects. I get an error along the lines of call to merge() on non object.

I actually tried to create an array of all of the collections, and then iterate through them, while checking their validity, but it didn't work and I feel it wasn't very elegant.

How can I elegantly iterate through this process of merging multiple collections, while taking into account that some or all of the collections might be empty or invalid? Appreciated!

Answer 1

What I ended up doing was separating each step. It was the merge chaining that was killing it, because some or all of the collections could have been invalid.

$allItems = new \Illuminate\Database\Eloquent\Collection; //Create empty collection which we know has the merge() method $allItems = $allItems->merge($collection1); $allItems = $allItems->merge($collection2); $allItems = $allItems->merge($collection3); $allItems = $allItems->merge($collection4); 

Answer 2

I had the same question, so I solved it in the following way:

$clients = ClientAccount::query()->get(); $admins = AdminAccount::query()->get();  $users = collect($clients)->merge($admins)->merge($anotherCollection)->merge(...);