COW 🐄 in Rust 🦀

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pub enum Cow<'a, B>
where
    B: 'a + ToOwned + ?Sized,
{
    Borrowed(&'a B),
    Owned(<B as ToOwned>::Owned),
}

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#[derive(CandidType, Deserialize, Clone)]
struct LogoResult {
    logo_type: Cow<'static, str>,
    data: Cow<'static, str>,
}

// ...
const DEFAULT_LOGO: LogoResult = LogoResult {
    data: Cow::Borrowed(include_base64!("logo.png")), //&str
    logo_type: Cow::Borrowed("image/png"), //&str
};

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fn remove_whitespaces(s: &str) -> String {
    s.to_string().replace(' ', "")
}

fn main() {
    let value = remove_whitespaces("Hello world!");
    println!("{}", value);
}

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use std::borrow::Cow;

fn remove_whitespaces(s: &str) -> Cow<str> {
    if s.contains(' ') {
        Cow::Owned(s.to_string().replace(' ', ""))
    } else {
        Cow::Borrowed(s)
    }
}

fn main() {
    let value = remove_whitespaces("Hello world!");
    println!("{}", value);
}