src/test/ui/single-use-lifetime/one-use-in-struct.rs

// Test that we do not warn for named lifetimes in structs,
// even when they are only used once (since to not use a named
// lifetime is illegal!)
//
// check-pass

#![deny(single_use_lifetimes)]
#![allow(dead_code)]
#![allow(unused_variables)]

struct Foo<'f> {
    data: &'f u32,
}

enum Bar<'f> {
    Data(&'f u32),
}

trait Baz<'f> {}

// `Derive`d impls shouldn't trigger a warning, either (Issue #53738).
#[derive(Debug)]
struct Quux<'a> {
    priors: &'a u32,
}

fn main() {}