arrays - Merge two Eloquent Collections and remove all duplicates.

Question

I have two arrays, $user_roles and $global_roles. I want to make a new array, let's call it $available_roles, where it can be equated as the items in $global_roles less the items in the $user_roles

I have the following code to do it to a normal array. $available_roles = array_unique(array_merge($global_roles, $user_roles), SORT_REGULAR);

This is proving to be problematic due to the fact that Laravel does not use traditional arrays when one executes a query, it uses Eloquent Collections.

What other ideas do you guys have?

Answer 1

This is fairly simple. You can use the Collection's merge method:

$available_roles = $global_roles->merge($user_roles);

Because merge internally uses an associative array (dictionary) that uses the id as key, this should automatically remove duplicates.

Anyways though, you can remove duplicates in a collection using unique:

$uniqueCollection = $collection->unique();

---

Now that was for merging what you're actually are looking for is the difference between two collections. You can do this in two ways:

$available_roles = $user_roles->diff($global_roles);

or

$available_roles = $global_roles->except($user_roles->modelKeys());