What best practices should be followed when updating PHP code to be compatible with PHP 7, especially in cases involving template classes and loops?

When updating PHP code to be compatible with PHP 7, especially in cases involving template classes and loops, it is important to address any deprecated features or syntax changes. One common issue is the use of the "each()" function within loops, which has been deprecated in PHP 7. To resolve this, you can replace the "each()" function with a combination of "current()", "key()", and "next()" functions to iterate over arrays.

// Before PHP 7
while(list($key, $value) = each($array)) {
    // loop logic
}

// After PHP 7
reset($array);
while(($key = key($array)) !== null) {
    $value = current($array);
    next($array);
    // loop logic
}