我有一个值,我想在我自己的类型中存储该值以及对该值内部内容的引用:
struct Thing {
count: u32,
}
struct Combined<'a>(Thing, &'a u32);
fn make_combined<'a>() -> Combined<'a> {
let thing = Thing { count: 42 };
Combined(thing, &thing.count)
}
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有时候,我有一个值,我想在同一个结构中存储该值和对该值的引用:
struct Combined<'a>(Thing, &'a Thing);
fn make_combined<'a>() -> Combined<'a> {
let thing = Thing::new();
Combined(thing, &thing)
}
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有时,我甚至没有参考该值,我得到同样的错误:
struct Combined<'a>(Parent, Child<'a>);
fn make_combined<'a>() -> Combined<'a> {
let parent = Parent::new();
let child = parent.child();
Combined(parent, child)
}
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在每种情况下,我都会收到一个错误,即其中一个值"活不够长".这个错误是什么意思?