59 lines
834 B
Rust
59 lines
834 B
Rust
// run-pass
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#![allow(dead_code)]
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#![allow(illegal_floating_point_literal_pattern)]
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#[repr(u32)]
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enum Tag {
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I,
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F,
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}
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#[repr(C)]
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union U {
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i: i32,
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f: f32,
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}
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#[repr(C)]
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struct Value {
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tag: Tag,
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u: U,
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}
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fn is_zero(v: Value) -> bool {
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unsafe {
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match v {
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Value { tag: Tag::I, u: U { i: 0 } } => true,
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Value { tag: Tag::F, u: U { f: 0.0 } } => true,
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_ => false,
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}
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}
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}
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union W {
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a: u8,
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b: u8,
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}
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fn refut(w: W) {
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unsafe {
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match w {
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W { a: 10 } => {
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panic!();
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}
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W { b } => {
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assert_eq!(b, 11);
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}
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}
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}
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}
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fn main() {
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let v = Value { tag: Tag::I, u: U { i: 1 } };
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assert_eq!(is_zero(v), false);
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let w = W { a: 11 };
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refut(w);
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}
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