28 lines
732 B
Rust
28 lines
732 B
Rust
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use std::io;
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struct MyError(()); // doesn't implement Debug
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#[derive(Debug)]
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struct MyErrorWithParam<T> {
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x: T
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}
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fn main() {
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let res: Result<i32, ()> = Ok(0);
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let _ = res.unwrap();
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res.ok().expect("disaster!");
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// the following should not warn, since `expect` isn't implemented unless
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// the error type implements `Debug`
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let res2: Result<i32, MyError> = Ok(0);
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res2.ok().expect("oh noes!");
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let res3: Result<u32, MyErrorWithParam<u8>>= Ok(0);
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res3.ok().expect("whoof");
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let res4: Result<u32, io::Error> = Ok(0);
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res4.ok().expect("argh");
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let res5: io::Result<u32> = Ok(0);
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res5.ok().expect("oops");
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let res6: Result<u32, &str> = Ok(0);
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res6.ok().expect("meh");
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}
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