mirror of https://github.com/rust-lang/rust
27 lines
831 B
Rust
27 lines
831 B
Rust
pub trait EdgeTrait<N> {
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fn target(&self) -> N;
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}
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pub trait Graph<'a> {
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type Node;
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type Edge: EdgeTrait<Self::Node>;
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type NodesIter: Iterator<Item = Self::Node> + 'a;
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type EdgesIter: Iterator<Item = Self::Edge> + 'a;
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fn nodes(&'a self) -> Self::NodesIter;
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fn out_edges(&'a self, u: &Self::Node) -> Self::EdgesIter;
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fn in_edges(&'a self, u: &Self::Node) -> Self::EdgesIter;
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fn out_neighbors(&'a self, u: &Self::Node) -> Box<dyn Iterator<Item = Self::Node>> {
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Box::new(self.out_edges(u).map(|e| e.target()))
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//~^ ERROR lifetime may not live long enough
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}
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fn in_neighbors(&'a self, u: &Self::Node) -> Box<dyn Iterator<Item = Self::Node>> {
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Box::new(self.in_edges(u).map(|e| e.target()))
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//~^ ERROR lifetime may not live long enough
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}
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}
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fn main() {}
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