{"ast_node_type":"other","tokens":[{"end":99,"kind":"keyword","start":0,"text":"len.and_then(|len|"}]}
                        len.and_then(|len| len.checked_sub((prefix.len() + suffix.len()) as u128));
                    let len =
                    TyKind::Array(elem_ty.clone(), usize_const(self.db, len, self.resolver.krate()))