fn new() -> Self

fn with_path(path: impl Into<PathBuf>) -> Self

fn save(&mut self, plan: Plan) -> ()

fn load(&self, id: &str) -> Option<&Plan>

fn load_mut(&mut self, id: &str) -> Option<&mut Plan>

fn delete(&mut self, id: &str) -> Option<Plan>

fn list(&self) -> Vec<&Plan>

fn count(&self) -> usize

fn persist(&self) -> std::io::Result<()>

fn restore(&mut self) -> std::io::Result<()>