环境
- Time 2022-12-03
- WSL-Ubuntu 22.04
- CLAP 4.0.29
前言
说明
参考：https://docs.rs/clap/latest/clap/index.html
目标
使用注解来验证参数的值。
Cargo.toml
[package]
edition = "2021"
name = "game"
version = "1.0.0"[dependencies]
clap = {version = "4", features = ["derive"]}
main.rs
use std::ops::RangeInclusive;use clap::{Parser, ValueEnum};/// 命令行参数
#[derive(Parser)]
#[command(author, version, about, long_about = None)]
struct Args {/// 编号#[arg(value_parser = clap::value_parser!(u8).range(0..=200))]number: u8,/// 性别#[arg(value_enum)]sex: Sex,/// 年龄#[arg(value_parser = age_in_range)]age: u8,
}#[derive(Clone, Debug, ValueEnum)]
enum Sex {Man,Woman,
}const AGE_RANGE: RangeInclusive<usize> = 0..=200;fn age_in_range(age: &str) -> Result<u8, String> {let age: usize = age.parse().map_err(|_| format!("`{}` isn't a number", age))?;if AGE_RANGE.contains(&age) {Ok(age as u8)} else {Err(format!("Age not in range {}-{}",AGE_RANGE.start(),AGE_RANGE.end()))}
}fn main() {let args = Args::parse();println!("编号是：{:?}", args.number);println!("性别是：{:?}", args.sex);println!("年龄是：{:?}", args.age);
}
查看帮助
root@jiangbo12490:~/git/game# cargo run -- -hCompiling game v1.0.0 (/root/git/game)Finished dev [unoptimized + debuginfo] target(s) in 0.54sRunning `target/debug/game -h`
命令行参数Usage: game <NUMBER> <SEX> <AGE>Arguments:<NUMBER> 编号<SEX> 性别 [possible values: man, woman]<AGE> 年龄Options:-h, --help Print help information-V, --version Print version information
使用
root@jiangbo12490:~/git/game# cargo run -- 1 man 44Finished dev [unoptimized + debuginfo] target(s) in 0.01sRunning `target/debug/game 1 man 44`
编号是：1
性别是：Man
年龄是：44
总结
使用注解来验证了参数的范围，自定义验证以及枚举类型的验证。