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extern crate chrono;
extern crate clap;
use clap::{App,Arg};
use chrono::{DateTime}; // date type
use chrono::{Local}; // timezone types
struct Clock;
impl Clock {
fn get() -> DateTime<Local> {
Local::now()
}
fn set() -> ! {
unimplemented!()
}
}
fn main() {
let app = App::new("clock")
.version("0.1")
.about("Gets and sets (aspirationally) the time.")
.arg(Arg::with_name("action")
.takes_value(true)
.possible_values(&["get", "set"])
.default_value("get"))
.arg(Arg::with_name("std")
.short("s")
.long("use-standard")
.takes_value(true)
.possible_values(&["rfc2822", "rfc3339", "timestamp"])
.default_value("rfc3339"))
.arg(Arg::with_name("datetime")
.help("When <action> is 'set', apply <datetime>. Otherwise, ignore."));
let args = app.get_matches();
let action = args.value_of("std").unwrap(); // default_value() has been supplied,
let std = args.value_of("std").unwrap(); // so it's safe to use .unwrap()
if action == "set" {
unimplemented!() // break early
}
let now = Clock::get();
match std {
"timestamp" => println!("{}", now.timestamp()),
"rfc2822" => println!("{}", now.to_rfc2822()),
"rfc3339" => println!("{}", now.to_rfc3339()),
_ => unreachable!(),
}
}
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