[SR-Users] Question - Kamailio script and how the return code from a command export is handled as a boolean?

Hello, I have a question regarding Kamailio script and how the return code from a command export is handled as a boolean. In Kamailio script, see this example: if (!jansson_get("method", $rb, "$var(method)")) { xhttp_reply("400", "Bad Request", "", ""); exit; } This code works, but I'm not sure why. Command "jansson_get" returns 1 if successful, and -1 if fails. Both values should be false. Which I can see when testing with this: $var(r) = jansson_get("method", $rb, "$var(method)"); xlog("L_INFO", "jansson_get r: [$var(r)]\n"); if (!$var(r)) { xlog("L_INFO", "jansson_get r: [$var(r)] => FALSE\n"); } else { xlog("L_INFO", "jansson_get r: [$var(r)] => TRUE\n"); } In all cases, the result is always TRUE. Is there some kind of "magic" conversion when directly checking the return of a command in Kamailio script ? With KEMI python, the equivalent does not work: if not KSR.jansson.get("method", KSR.pv.get("$rb"), "$var(method)"): KSR.xhttp.xhttp_reply(400, "Bad Request", "", "") return 1 So I have to do the following instead: if KSR.jansson.get("method", KSR.pv.get("$rb"), "$var(method)") < 0: KSR.xhttp.xhttp_reply(400, "Bad Request", "", "") return 1 Thank you for your help. Regards, Nicolas. This message contains information that may be privileged or confidential and is the property of the Capgemini Group. It is intended only for the person to whom it is addressed. If you are not the intended recipient, you are not authorized to read, print, retain, copy, disseminate, distribute, or use this message or any part thereof. If you receive this message in error, please notify the sender immediately and delete all copies of this message.