Accessing/modifying a variable inside a lambda function in PHP – scope issue

I'm trying to filter an associative array using a lambda function in PHP. Here's what I'm doing:

Declare an empty array ($filteredItems) inside the lambda to store filtered results.
Loop through the original associative array, check each item against a condition (e.g., matching a key-value pair).
Append matching items to $filteredItems.
Return $filteredItems from the lambda.

However, when I try to var_dump($filteredItems) outside the lambda, I get an "undefined variable" error.

Problem:

I understand that $filteredItems is scoped to the lambda and inaccessible outside it, but can be accessed if it the variable is returned.
If the variable were declared outside the lambda, I could use the use keyword to access it, but here the variable is inside the lambda.
Even though I return $filteredItems, directly trying to access it later (e.g., for debugging) fails.

Question: How can I properly access or inspect the filtered array? Is my approach correct, or is there a better way to handle this?

(Note: I’m aware I could use array_filter(), but I’m trying to understand lambda scope in this context.)

Here’s my code

Lambda Functions