Online PHP editor | refs for GNWKP

<?php const READ = 0b001; const WRITE = 0b010; const EXECUTE = 0b100; function testBit($flags, $bit) { return !! ($flags & $bit); } function clearBit($flags, $bit) { return $flags ^ $bit; } function setBit($flags, $bit) { return $flags | $bit; } function toggleBit($flags, $bit) { return $flags ^ $bit; } $guest = READ; $user = READ | WRITE; $admin = READ | WRITE | EXECUTE; assert(!testBit($guest, WRITE)); assert(testBit(setBit($guest, WRITE), WRITE)); assert(testBit($user, WRITE)); assert(!testBit(clearBit($user, WRITE), WRITE)); $admin = toggleBit($admin, EXECUTE); assert(!testBit($admin, EXECUTE)); $admin = toggleBit($admin, EXECUTE); assert(testBit($admin, EXECUTE));