What are common methods for optimizing PHP code for performance?

One common method for optimizing PHP code for performance is to minimize the use of loops and instead use built-in array functions like array_map, array_filter, and array_reduce. These functions are optimized for performance and can often replace complex loops with a single function call.

// Example of optimizing code by using array_map instead of a loop
$numbers = [1, 2, 3, 4, 5];

// Inefficient loop
$newNumbers = [];
foreach ($numbers as $number) {
    $newNumbers[] = $number * 2;
}

// Optimized code using array_map
$newNumbers = array_map(function($number) {
    return $number * 2;
}, $numbers);