[Solved] What is wrong with this code?$arr = [1, 2, 3, 4]; $filtered = array_filter($arr, fn($n) => $n > 2); print_r($filtered);Output is empty array. | PHP

PHP - Array Functions

What is wrong with this code?

$arr = [1, 2, 3, 4];
$filtered = array_filter($arr, fn($n) => $n > 2);
print_r($filtered);

Output is empty array.

Aarray_filter does not work with arrow functions

BThe callback should return false for numbers > 2

CThe array must be passed by reference

DThe arrow function syntax requires PHP 7.4+, older versions fail

Step-by-Step Solution

Solution:

Step 1: Check PHP version compatibility
Arrow functions (fn) are supported from PHP 7.4 onwards.
Step 2: Understand why output is empty
If run on older PHP versions, arrow function syntax causes failure, resulting in empty output.
Final Answer:
The arrow function syntax requires PHP 7.4+, older versions fail -> Option D
Quick Check:
Arrow functions need PHP 7.4+ [OK]

Quick Trick: Use arrow functions only in PHP 7.4+ [OK]

Common Mistakes:

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What is wrong with this code?