src/test/ui/issues/issue-55796.rs

   1 pub trait EdgeTrait<N> {
   2     fn target(&self) -> N;
   3 }
   4
   5 pub trait Graph<'a> {
   6     type Node;
   7     type Edge: EdgeTrait<Self::Node>;
   8     type NodesIter: Iterator<Item = Self::Node> + 'a;
   9     type EdgesIter: Iterator<Item = Self::Edge> + 'a;
  10
  11     fn nodes(&'a self) -> Self::NodesIter;
  12     fn out_edges(&'a self, u: &Self::Node) -> Self::EdgesIter;
  13     fn in_edges(&'a self, u: &Self::Node) -> Self::EdgesIter;
  14
  15     fn out_neighbors(&'a self, u: &Self::Node) -> Box<Iterator<Item = Self::Node>> {
  16         Box::new(self.out_edges(u).map(|e| e.target()))
  17 //~^ ERROR cannot infer
  18     }
  19
  20     fn in_neighbors(&'a self, u: &Self::Node) -> Box<Iterator<Item = Self::Node>> {
  21         Box::new(self.in_edges(u).map(|e| e.target()))
  22 //~^ ERROR cannot infer
  23     }
  24 }