Online PHP editor | output for moET9

<?php //old code function v1($first, $last) { $result = trim($first); $lastName = trim($last); if ($lastName) { if (!empty($result)) { $result .= ','; } $result .= $lastName; } return $result; } //my function v2($first, $last) { return implode(",", [trim($first), trim($last)]); } //@Hunternnm function v3($first, $last) { if(strlen($first) > 0 && strlen($last) > 0) { return $first.",".$last; } if(strlen($first) > 0) { return $first; } else { return $last; } } //@NelinD function v4($first, $last) { return implode(',', array_filter([$first, $last], function ($string) { return trim($string); })); } function v($first, $last) { echo v1($first, $last); echo PHP_EOL; echo v2($first, $last); echo PHP_EOL; echo v3($first, $last); echo PHP_EOL; echo v4($first, $last); echo PHP_EOL; echo PHP_EOL; } v('first', 'last'); v('first', ''); v('first', ' ');