tzconvert/src/main.rs

use structopt::StructOpt;
use chrono::prelude::*;

/// timezone converter
///
/// Examples:
///
/// - tzconvert CET EST 2pm
///
/// - tzconvert Africa/Timbuktu America/Jamaica 18:30 --date 2021-11-03
///
#[derive(StructOpt, Debug)]
#[structopt(author = env!("CARGO_PKG_AUTHORS"))]
struct Opt {
    /// originating time zone
    #[structopt(value_name = "FROM TIMEZONE")]
    from: String,
    /// destination time zone
    #[structopt(value_name = "TO TIMEZONE")]
    to: String,
    /// time to convert (HH:MM or HH[:MM]am/HH[:MM]pm)
    #[structopt(value_name = "TIME")]
    time: String,

    /// specify the date on which the time lies; defaults to today
    #[structopt(long, short)]
    date: Option<NaiveDate>,
}

fn main() {
    let Opt { from, to, time, date } = Opt::from_args();
    tzconvert::convert(&from, &to, &time, date);
}