rust对话小程序

extern crate regex;

use std::io::Write;
use std::vec::Vec;
use std::io;
use std::time::UNIX_EPOCH;
use std::time::SystemTime;
use std::collections::HashMap;
use regex::Regex;

#[derive(Debug)]
struct Question {
    id:i64 ,
    que:String,
    ans:Vec<Answer>,
}
#[derive(Debug)]
struct Answer {
    ans: String,
    class:u8,//0-10
}
impl Question {
    fn new()-> Question {
        Question{
            id:timestamp1(),//时间戳
            que:String::new(),
            ans:Vec::new(),
        }       
    }
    fn set_que(&mut self,que:String) {
        self.que = que;
    }
    fn set_ans(&mut self,answer:Answer) {
        self.ans.push(answer);
    }
}

//***************************************************************
fn main(){  
    fn print_refs(x:&i32,y:&i32) {
        println!("{},{}", x,y);
    }
    let (four,nine) = (4,9);
    print_refs(&four,&nine);

}
//***************************************************************
fn creat_question(que:String,ans:String,class:u8) -> Question {
    let mut question = Question::new();
    question.set_que (que);
    question.set_ans(Answer{ans,class});
    question
}
//从用户输入创建一个问题和答案
fn creat_question_from_stdin() -> Question {
    let que = input_que();
    let ans = input_ans();
    let mut question = Question::new();
    question.set_que(que);
    question.set_ans(ans);
    question
}
//输入问题
fn input_que()->String {
    let mut buf = String::new();
    println!("请输入你的问题：", );
    read_from_stdin(&mut buf).unwrap();
    buf
}
//输入答案
fn input_ans() -> Answer {
    let mut buf2 =String::new();
    println!("请输入你的答案：", );
    read_from_stdin(&mut buf2).unwrap();

    let mut class =String::new();
    println!("请输入情感级别（0-10）", );
    read_from_stdin(&mut class).unwrap();
    let  class :u8= class.trim().parse().unwrap();
    Answer{ans:buf2,class:class}
}
//读取用户输入
fn read_from_stdin(buf: &mut String) -> io::Result<()> {
    try!(io::stdin().read_line(buf));
    Ok(())
}
//获取当前时间戳
fn timestamp1() -> i64 {
    let start = SystemTime::now();
    let since_the_epoch = start
        .duration_since(UNIX_EPOCH)
        .expect("Time went backwards");
    let ms = since_the_epoch.as_secs() as i64 * 1000i64 + (since_the_epoch.subsec_nanos() as f64 / 1_000_000.0) as i64;
    ms
}