{"ast_node_type":"other","tokens":[{"end":97,"kind":"keyword","start":0,"text":"///"}]}
/// but this is too complex to verify here. Also it's just a logic error if users get this wrong.
/// That usually means we have a &mut or *mut T output and compute derivatives wrt. that arg,
pub fn valid_ret_activity(mode: DiffMode, activity: DiffActivity) -> bool {