Online PHP editor | output for Y8C9h

<?php echo "'string'\n"; $r = json_decode("'string'"); var_dump($r, json_last_error(), json_last_error_msg()); echo "\"string\"\n"; $r = json_decode("\"string\""); var_dump($r, json_last_error(), json_last_error_msg()); echo "\n"; echo "100\n"; $r = json_decode("100"); // int var_dump($r, json_last_error(), json_last_error_msg()); echo "\n"; echo "1.\n"; $r = json_decode("1."); // float var_dump($r, json_last_error(), json_last_error_msg()); echo "\n"; echo "1.0\n"; $r = json_decode("1.0"); // float var_dump($r, json_last_error(), json_last_error_msg()); echo "\n"; echo ".5\n"; $r = json_decode(".5"); // float var_dump($r, json_last_error(), json_last_error_msg()); echo "\n"; echo "true\n"; $r = json_decode("true"); // bool var_dump($r, json_last_error(), json_last_error_msg());