Online PHP editor | refs for tlbTF

<?php echo "<?php\n\n"; foreach (['e', 'f', 'n', 'r', 't', 'v'] as $c) { echo "const {$c} = \"\\{$c}\";\n"; } for ($i = 0; $i < 256; $i++) { $str = str_pad(strtoupper(dechex($i)), 2, '0', STR_PAD_LEFT); $p1 = [$str[0]]; if ($str[0] >= 'A' && $str[0] <= 'F') { $p1[] = strtolower($str[0]); } $p2 = [$str[1]]; if ($str[1] >= 'A' && $str[1] <= 'F') { $p2[] = strtolower($str[1]); } foreach ($p1 as $c1) foreach ($p2 as $c2) echo "const x{$c1}{$c2} = \"\\x{$str}\";\n"; }