ortem.xyz/content/blog/rust-tricky-quiz.md

+++ title = "Tricky questions for any rust interview" draft = true date = "2022-08-18"

[taxonomies] tags = ["rust"] +++

Which type has variable result?

fn count_uppercase(s: &str) -> usize {
    let result = {
        let upper = s.chars().filter(|c| c.is_uppercase()).collect::<String>();
        return upper.len();
    };
}

Answer

result has '!' type or 'never type'. . Read more