【Rust】可选枚举（四）

环境

• Time 2022-03-25
• Rust 1.59.0

示例

get_or_insert_with

fn main() {
    let mut name = Some("JiangBo");
    println!("{:?}", name.get_or_insert_with(|| "Rust"));
}

take

fn main() {
    let mut name = Some("JiangBo");
    name.take();
    println!("{:?}", name);
}

replace

fn main() {
    let mut name = Some("JiangBo");
    name.replace("Rust");
    println!("{:?}", name);
}

zip

fn main() {
    let name = Some("JiangBo");
    println!("{:?}", name.zip(Some("Rust")));
}

copied

fn main() {
    let name = Some(&44);
    println!("{:?}", name.copied());
}

clone

fn main() {
    let name = Some(&44);
    println!("{:?}", name.clone());
}

transpose

fn main() {
    let name: Option<Result<&str, u32>> = Some(Ok("JiangBo"));
    println!("{:?}", name.transpose());
}

flatten

fn main() {
    let name = Some(Some("JiangBo"));
    println!("{:?}", name.flatten());
}

总结

了解了可选枚举中相关的一些方法。

附录