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//@ build-fail
//@ known-bug: #95134
//@ compile-flags: -Copt-level=0
//@ dont-check-failure-status
//@ dont-check-compiler-stderr
pub fn encode_num<Writer: ExampleWriter>(n: u32, mut writer: Writer) -> Result<(), Writer::Error> {
if n > 15 {
encode_num(n / 16, &mut writer)?;
}
Ok(())
}
pub trait ExampleWriter {
type Error;
}
impl<'a, T: ExampleWriter> ExampleWriter for &'a mut T {
type Error = T::Error;
}
struct EmptyWriter;
impl ExampleWriter for EmptyWriter {
type Error = ();
}
fn main() {
encode_num(69, &mut EmptyWriter).unwrap();
}
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