Function JS_IsNull

third-party/quickjs/include/quickjs/quickjs.h:583–585

}

static inline JS_BOOL JS_IsNull(JSValueConst v) {
    return JS_VALUE_GET_TAG(v) == JS_TAG_NULL;
}

static inline JS_BOOL JS_IsUndefined(JSValueConst v) {
    return JS_VALUE_GET_TAG(v) == JS_TAG_UNDEFINED;