PHP 8.1: Inconsistent Results When Using array_map with Callable Class Methods
I'm experiencing inconsistent results when using `array_map` with a callable method from a class in PHP 8.1. I have a class `DataProcessor` with a method `process` that takes an array and performs some transformations. When I try to use `array_map` to apply this method to an array of items, I sometimes get unexpected null values in the results. Here’s what my code looks like: ```php class DataProcessor { public function process($item) { // Simulate a process that might unexpected result in certain conditions if (empty($item)) { return null; // Simulating a failure } return strtoupper($item); } } $data = ['apple', '', 'banana', 'cherry']; $processor = new DataProcessor(); $results = array_map([$processor, 'process'], $data); var_dump($results); ``` When I run this code, I get the following output: ``` array(4) { [0]=> string(5) "APPLE" [1]=> NULL [2]=> string(6) "BANANA" [3]=> string(6) "CHERRY" } ``` The method returns null for the empty string as expected, but in certain scenarios, I also see that `array_map` returns null for valid inputs when the method is invoked via the callable. I've confirmed that the input data is consistent. I tried debugging with additional logging inside the `process` method, and it seems to be called correctly with the expected values. I also tried using an anonymous function as a workaround: ```php $results = array_map(function($item) use ($processor) { return $processor->process($item); }, $data); ``` This approach seems to work without any issues, but I’d prefer to use the class method directly for clarity and maintainability. Is there something specific to class method visibility or callable handling in PHP 8.1 that I might be missing here? Any insights would be greatly appreciated!