{"ast_node_type":"other","tokens":[{"end":86,"kind":"keyword","start":0,"text":".and_then(|at|"}]}
            .and_then(|at| fn_name.is_char_boundary(at).then(|| fn_name.split_at(at)))
            .checked_sub(param_name.len())
            .is_some_and(|(prefix, suffix)| {