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42 lines
820 B
Rust
42 lines
820 B
Rust
//@ check-pass
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#![feature(never_type, exhaustive_patterns)]
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#![warn(unreachable_code)]
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#![warn(unreachable_patterns)]
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enum Void {}
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impl From<Void> for i32 {
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fn from(v: Void) -> i32 {
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match v {}
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}
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}
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fn bar(x: Result<!, i32>) -> Result<u32, i32> {
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x?
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}
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fn foo(x: Result<!, i32>) -> Result<u32, i32> {
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let y = (match x { Ok(n) => Ok(n as u32), Err(e) => Err(e) })?;
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//~^ WARN unreachable pattern
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//~| WARN unreachable expression
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Ok(y)
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}
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fn qux(x: Result<u32, Void>) -> Result<u32, i32> {
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Ok(x?)
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}
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fn vom(x: Result<u32, Void>) -> Result<u32, i32> {
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let y = (match x { Ok(n) => Ok(n), Err(e) => Err(e) })?;
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//~^ WARN unreachable pattern
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Ok(y)
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}
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fn main() {
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let _ = bar(Err(123));
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let _ = foo(Err(123));
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let _ = qux(Ok(123));
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let _ = vom(Ok(123));
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}
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