mirror of https://github.com/rust-lang/rust
40 lines
1006 B
Rust
40 lines
1006 B
Rust
#![feature(box_patterns)]
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struct HTMLImageData {
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image: Option<String>,
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}
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struct ElementData {
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kind: Box<ElementKind>,
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}
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enum ElementKind {
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HTMLImageElement(HTMLImageData),
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}
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enum NodeKind {
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Element(ElementData),
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}
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struct NodeData {
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kind: Box<NodeKind>,
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}
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fn main() {
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let mut id = HTMLImageData { image: None };
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let ed = ElementData { kind: Box::new(ElementKind::HTMLImageElement(id)) };
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let n = NodeData { kind: Box::new(NodeKind::Element(ed)) };
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// n.b. span could be better
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match n.kind {
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box NodeKind::Element(ed) => match ed.kind {
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//~^ ERROR non-exhaustive patterns
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//~| NOTE the matched value is of type
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//~| NOTE match arms with guards don't count towards exhaustivity
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//~| NOTE pattern `box ElementKind::HTMLImageElement(_)` not covered
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//~| NOTE `Box<ElementKind>` defined here
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box ElementKind::HTMLImageElement(ref d) if d.image.is_some() => true,
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},
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};
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}
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