Online PHP editor | refs for VYIFd

<?php $a = [ 'a' => 'some value', 'b' => 'some value', 'c' => 'some value' ]; $b = [ 'a' => 'another value', 'd' => 'another value', 'e' => 'another value', 'f' => 'another value' ]; $c = [ 'b' => 'some more value', 'x' => 'some more value', 'y' => 'some more value', 'z' => 'some more value' ]; $defaults = array_fill_keys(array_keys($a + $b + $c), ''); var_export( array_map(fn($row) => array_merge($defaults, $row), [$a, $b, $c]) );