rngstr 0.3.0

macro_rules! parse_args {
    ($name:ident, $args:expr, $($num:literal => $t:ty),+) => {
        ($($args.get($num).ok_or(format!("expected argument '{}' at '{}'", $num.to_string(), stringify!($name)))?.parse::<$t>().map_err(|_| {"parsing".to_string()})?),+)
    };
}

macro_rules! fn_types {
    ($($t:ident)+) => {
        $(pub fn $t(args: &Vec<String>) -> Result<String, String> {
            if args.get(0).is_some() && args.get(1).is_some() {
                let (start, end) = parse_args!($t, args,
                    0 => $t,
                    1 => $t
                );
                Ok(thread_rng().gen_range(start..end).to_string())
            } else {
                Ok(thread_rng().gen::<$t>().to_string())
            }

        })+
    };
}

macro_rules! builtin_types {
    ($($t:ident)+) => {
        [$(
            (
                stringify!($t).to_string(),
                Proc::Builtin {
                    params: Some(Params {
                        body: "".into(),
                        params: vec!["start".into(), "end".into()],
                    }),
                    f: builtins::$t,
                }
            ),
        )+]
    };
}