#![allow(unused)]
struct Foo {
    text1: Option<String>,
    text2: String,
}

impl Foo {
    pub fn set_text(&mut self) {
        if let Some(ref mut t) = self.text1 {
            t.pop();
            self.set_text2();
        }
    }

    fn set_text2(&mut self) {
        self.text2.pop();
        println!("{}", self.text2);
    }
}
fn main() {
    let mut foo = Foo {
        text1: Some("hello, world!".to_string()),
        text2: "I am 谭越".to_string(),
    };

    foo.set_text();
}