I have following code:

impl StringExt for String {
    fn replacement(&self) -> Self {
        let replaced = NEWLINE_RE.replace_all(self, "\n");
        let replaced = QUOTES_RE.replace_all(&replaced, "");
        let replaced = LINKS_RE.replace_all(&replaced, |caps: &Captures| {
            let caps_str: Vec<_> = caps
                .iter()
                .flat_map(|c| c.map(|c| c.as_str()))
                .collect();
            caps_str.last().unwrap()
            //format!("{}", caps_str.last().unwrap())
        });
        replaced.into()
    }
}

When I try to compile I'm getting following error about lifetimes:

error: lifetime may not live long enough
  --> src/main.rs:72:13
   |
67 |         let replaced = LINKS_RE.replace_all(&replaced, |caps: &Captures| {
   |                                                         ----           - return type of closure is &'2 &str
   |                                                         |
   |                                                         has type `&regex::Captures<'1>`
...
72 |             caps_str.last().unwrap()
   |             ^^^^^^^^^^^^^^^^^^^^^^^^ returning this value requires that `'1` must outlive `'2`

error[E0515]: cannot return value referencing local variable `caps_str`
  --> src/main.rs:72:13
   |
72 |             caps_str.last().unwrap()
   |             --------^^^^^^^^^^^^^^^^
   |             |
   |             returns a value referencing data owned by the current function
   |             `caps_str` is borrowed here

I can easily workaround it by using format, but of course I would like to know how to this proper. Using caps_str.last().cloned().unwrap() does not work either

Thanks!

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