Returning repositories head object in a function

[da-moon]

Hello!
I have a newb question. I have been trying to write a function that would return my repositories' HEAD (gix::Head) . I can't figure out how to deal with the borrow checker though as it is returning the following error

error[E0515]: cannot return value referencing local variable `r`
  --> workspaces/version/src/lib.rs:28:5
   |
27 |     let h = r.head()?.to_owned();
   |             - `r` is borrowed here
28 |     Ok(h)
   |     ^^^^^ returns a value referencing data owned by the current function

Here is the function :

fn head<'a>() -> Result<gix::Head<'a>, Box<dyn Error>> {
    let r = gix::discover(Path::new(""))?;
    let r = Box::new(r);
    let h = r.head()?;
    Ok(h)
}

Can someone please tell me how I can address this problem ?
Thank you

[Byron]

gix::Head is actually gix::Head<'repo>, which means it borrows the repository that is created a couple of lines earlier, and which is dropped at the end of the function. There are lot's of great learning resources for Rust that help understand that borrow checker, and I strongly recommend giving these a shot.

Writing a function like you want it probably doesn't make much sense, but for completeness, here it is:

fn head(repo: &gix::Repository) -> Result<gix::Head<'_>, Box<dyn Error>> {
    Ok(r.head()?)
}

[da-moon]

so correct me if I am wrong but there is no proper way to create the repo inside the function, right? I wanted to keep the function signature as something like fn head() -> Result<gix::Head<'_>, Box<dyn Error>> and not pass in a reference to the repo object that was created out of the function's scope.

I tried wrapping the Repository object and Head in Rc and Box but none of them worked.