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