46 lines
1.2 KiB
Rust
46 lines
1.2 KiB
Rust
// Copyright 2012-2013 The Rust Project Developers. See the COPYRIGHT
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// file at the top-level directory of this distribution and at
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// http://rust-lang.org/COPYRIGHT.
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//
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// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
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// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
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// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
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// option. This file may not be copied, modified, or distributed
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// except according to those terms.
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#![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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_ => panic!("WAT") //~ ERROR unreachable pattern
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};
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}
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