clap/examples/tutorial_derive/04_03_relations.rs

75 lines
1.8 KiB
Rust

use clap::{Args, Parser};
#[derive(Parser)]
#[command(version, about, long_about = None)]
struct Cli {
#[command(flatten)]
vers: Vers,
/// some regular input
#[arg(group = "input")]
input_file: Option<String>,
/// some special input argument
#[arg(long, group = "input")]
spec_in: Option<String>,
#[arg(short, requires = "input")]
config: Option<String>,
}
#[derive(Args)]
#[group(required = true, multiple = false)]
struct Vers {
/// set version manually
#[arg(long, value_name = "VER")]
set_ver: Option<String>,
/// auto inc major
#[arg(long)]
major: bool,
/// auto inc minor
#[arg(long)]
minor: bool,
/// auto inc patch
#[arg(long)]
patch: bool,
}
fn main() {
let cli = Cli::parse();
// Let's assume the old version 1.2.3
let mut major = 1;
let mut minor = 2;
let mut patch = 3;
// See if --set_ver was used to set the version manually
let vers = &cli.vers;
let version = if let Some(ver) = vers.set_ver.as_deref() {
ver.to_string()
} else {
// Increment the one requested (in a real program, we'd reset the lower numbers)
let (maj, min, pat) = (vers.major, vers.minor, vers.patch);
match (maj, min, pat) {
(true, _, _) => major += 1,
(_, true, _) => minor += 1,
(_, _, true) => patch += 1,
_ => unreachable!(),
};
format!("{major}.{minor}.{patch}")
};
println!("Version: {version}");
// Check for usage of -c
if let Some(config) = cli.config.as_deref() {
let input = cli
.input_file
.as_deref()
.unwrap_or_else(|| cli.spec_in.as_deref().unwrap());
println!("Doing work using input {input} and config {config}");
}
}