Chapter 10.3. Third elision rule.

• I have checked the latest main branch to see if this has already been fixed
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URL to the section(s) of the book with this problem:
https://doc.rust-lang.org/book/ch10-03-lifetime-syntax.html

Description of the problem:
This has to do with the example provided of the 3rd elision rule in action:

impl<'a> ImportantExcerpt<'a> {
    fn announce_and_return_part(&self, announcement: &str) -> &str {
        println!("Attention please: {}", announcement);
        self.part
    }
}

I'm new to Rust. My immediate thought in reading this example was "Oh no, what if the function returns 'announcement'? Assigning self's lifetime to the output reference seems very dangerous here. What if 'announcement' is returned instead?" I was so concerned, I tried it. And was very relieved that the compiler reported an error.

Suggested fix:
I would suggest stating that the 3rd elision is making the assumption that self (or some component thereof) will be returned. And although the compiler will in all cases apply the 3rd elision rule to a method signature like the above, the code will not compile if that assumption is violated. This is an important difference from the first two elision rules. I believe they can safely be applied without any particular assumptions about the body of the function. Otherwise put, I don't think either of them could cause code to fail to compile.

Start with the linked Chapter 10.3 section and inspect the source for the announce_and_return_part example. Clarify the third elision rule's assumption about returning data tied to self, and explain what happens when the function body violates that assumption. Done when the example and surrounding explanation address this distinction clearly.