pub async fn command (core: &Core, command: &str, msg: &Message, words: &[String]) -> Result<()> {
	let mut conn = core.db.begin().await.stack()?;
	let sender = msg.sender.get_user_id()
		.stack_err("Ignoring unreal users.")?;
	let reply = if words.len() == 1 {
		match words[0].parse::<i32>() {
			Err(err) => format!("I need a number.\n{}", &err).into(),
			Err(err) => format!("I need a number.\n{}", err).into(),
			Ok(number) => match command {
				"/check" => core.check(number, false, None).await
					.context("Channel check failed.")?.into(),
				"/clean" => conn.clean(number, sender).await.stack()?,
				"/enable" => conn.enable(number, sender).await.stack()?.into(),
				"/delete" => conn.delete(number, sender).await.stack()?,
				"/disable" => conn.disable(number, sender).await.stack()?.into(),

		let response = builder.send().await.stack()?;
		#[cfg(debug_assertions)]
		{
			let headers = response.headers();
			let expires = headers.get(EXPIRES);
			let cache = headers.get(CACHE_CONTROL);
			if expires.is_some() || cache.is_some() {
				println!("{} {} {:?} {:?} {:?}", Local::now().to_rfc2822(), &source.url, last_scrape, expires, cache);
				println!("{} {} {:?} {:?} {:?}", Local::now().to_rfc2822(), source.url, last_scrape, expires, cache);
			}
		}
		let status = response.status();
		let content = response.bytes().await.stack()?;
		match rss::Channel::read_from(&content[..]) {
			Ok(feed) => {
				for item in feed.items() {