Function batch 

pub fn batch(cmds: Vec<Option<Cmd>>) -> Option<Cmd>

Batch multiple commands to run concurrently.

Commands in a batch run in parallel with no ordering guarantees. Use this to return multiple commands from an update function.

Example

use bubbletea::{Cmd, Message, batch};

let cmd = batch(vec![
    Some(Cmd::new(|| Message::new("first"))),
    Some(Cmd::new(|| Message::new("second"))),
]);