Hello!
The behavior you're observing is due to the fact that objects in PHP are passed by reference by default. This means that when you pass an object to a function, you're actually passing a reference to the original object, not a copy of it. Therefore, any changes you make to the object's properties within the function will affect the original object.
In your code, $users is a collection of user objects. When you pass $users to the addThreeYearsToUsers function and iterate over it, you're modifying the properties of the objects within that collection. Since objects are reference types, the original user objects in the $users collection are updated.
Here's a modified version of your code that clarifies this concept:
$users = Users::all();
function addThreeYearsToUsers($users) {
foreach ($users as $user) {
$user->age += 3; // This modifies the original user object's age property
}
}
addThreeYearsToUsers($users);
dd($users);
If you want to avoid modifying the original objects, you would need to clone each object before making changes to it. Here's how you could do that:
$users = Users::all();
function addThreeYearsToUsers($users) {
$modifiedUsers = [];
foreach ($users as $user) {
$clonedUser = clone $user; // Create a shallow copy of the user object
$clonedUser->age += 3; // Modify the cloned object
$modifiedUsers[] = $clonedUser; // Add the cloned object to the new array
}
return $modifiedUsers; // Return the new array with modified cloned objects
}
$usersWithAddedYears = addThreeYearsToUsers($users);
dd($usersWithAddedYears); // This will show the modified ages
dd($users); // This will show the original ages, unchanged
In this modified version, the original $users array remains unchanged, and a new array $usersWithAddedYears contains the cloned and modified user objects.
