3 #![feature(box_syntax)]
5 use std::collections::HashMap;
7 trait Graph<Node, Edge> {
12 impl<E> Graph<isize, E> for HashMap<isize, isize> {
16 fn g(&self, _e: isize) {
22 let g : Box<HashMap<isize,isize>> = box HashMap::new();
23 let _g2 : Box<dyn Graph<isize,isize>> = g as Box<dyn Graph<isize,isize>>;