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This post is auto-generated from RSS feed The Rust Programming Language Forum - Latest topics. Source: Understanding ? in Map/Filter Closures

I am writing a small bit of code to simply list out all the files in a directory, and as far as I can tell, this seems like the correct way to do that:

fn get_files(p: &Path) -> Result<Vec<PathBuf>, io::Error> {
    read_dir(p)?
        .into_iter()
        .map(|f| f.map(|f| f.path()))
        .filter(|f| f.as_ref().is_ok_and(|f| f.is_file()))
        .collect()
}

However, my naive rust-beginner brain would have preferred to write:

fn get_files(p: &Path) -> Result<Vec<PathBuf>, io::Error> {
    read_dir(p)?
        .into_iter()
        .map(|f| f?.path())
        .filter(|f| f?.is_file())
        .collect()
}

If I understand the compiler messages, this is not allowed because then the closures are then returning PathBuff and bool rather than Results.

Given that, there a better/more ergonomic way to approach this that I'm missing (especially since I'm collecting the Results anyway), or is this the preferred approach?

Thank you for any help!

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