35 lines
738 B
Rust
35 lines
738 B
Rust
#![feature(box_patterns)]
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#![feature(box_syntax)]
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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 ElementKind::HTMLImageElement(id) };
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let n = NodeData {kind : box 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 { //~ ERROR non-exhaustive patterns
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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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