GObject.type_get_type_registration_serial

function type_get_type_registration_serial(): Number(guint) {
    // Gjs wrapper for g_type_get_type_registration_serial()
}
  

Returns an opaque serial number that represents the state of the set of registered types. Any time a type is registered this serial changes, which means you can cache information based on type lookups (such as GObject.type_from_name) and know if the cache is still valid at a later time by comparing the current serial with the one at the type lookup.

Since 2.36