pub trait Edge<T: PartialOrd + Debug> {
// Required methods
fn ver_a(&self) -> &Vertice<T>;
fn ver_b(&self) -> &Vertice<T>;
fn distance(&self) -> &usize;
// Provided method
fn is_loop(&self) -> bool { ... }
}pub trait Edge<T: PartialOrd + Debug> {
// Required methods
fn ver_a(&self) -> &Vertice<T>;
fn ver_b(&self) -> &Vertice<T>;
fn distance(&self) -> &usize;
// Provided method
fn is_loop(&self) -> bool { ... }
}