foo.rs

pub struct RefList<T: 'local> {
    // Use this arena to create the node elements in the list.
    node_arena: TypedArena<T>

    // Store the last object allocated from the `node_arean` in this field.
    list_tail: Option<&'local mut T>,
}

impl<T> RefList<T: 'local> {
    fn new(capacity: usize) -> RefList<T> {
        RefList {
            list_tail: None,
            node_arena: TypedArena::with_capacity(capacity)
        }
    }

    fn push_back(&mut self, new_tail: T) {
      // Allocate the new value `new_tail` inside of the arena and store
      // the recieved object from the arena on the `list_tail`.
      self.list_tail = Some(self.node_arena.alloc(T));
    }
}