Hi all,

I can not get my head around this error:

   --> src/collection.rs:223:32
    |
222 |                     if r.exists() && r.is_dir() && let Ok(c) = Self::open(&r.to_path_buf()) {
    |                                                                            --------------- temporary value created here
223 |                         return Ok(c);
    |                                ^^^^^ returns a value referencing data owned by the current function

I think I understood this explanation. I can not pass some reference from within some method to its caller for that's a dangling reference. Same is true for any value / parameter inside a method that gets passed on to other (inner) methods. That parameter still is local to the method an can not be returned.

I tried to get a reduced implementation of my own sources. The reduction looks like this and works well.

use std::path::PathBuf;
use std::path::Path;
struct Collection {
    path: PathBuf,
}
impl Collection {
    pub fn new(r: &Path) -> Result<Collection, String> {
        if r.exists() && r.is_dir() && let Ok(c) = Self::open(&r.to_path_buf()) {
            return Ok(c);
        }
        Ok(Collection { path: r.to_path_buf(), })
    }
    pub fn open(r: &PathBuf) -> Result<Collection, String> {
        Ok(Collection { path: r.to_path_buf(), })
    }
}
fn main() {
    let _ = Collection::new(Path::new("."));
}

I have no idea why my source (line 222 above) does not compile. I think it's the open-method of mine. Looking at that method - what am I searching for? What causes line 222 to fail? I'm using plenty of clone within my open to create owned data that will not dangle. What else can I check for?

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