{"ast_node_type":"other","tokens":[{"end":67,"kind":"keyword","start":0,"text":"Some(len)"}]}
                    Some(len) => is_ty_must_use(cx, ty, expr, span)
                    // If the array is definitely non-empty, we can do `#[must_use]` checking.
                        .map(|inner| MustUsePath::Array(Box::new(inner), len)),