Esta não é uma solução para o meu problema. A resposta sugerida substitui os valores por Nones. Eu literalmente preciso que o tamanho do meu vetor seja reduzido.
MRE:
use tokio::sync::mpsc;
#[tokio::main]
async fn main() {
// Pits the singers against each other...
// Please do not get confused by the type of the sender used in here.
// This still will showcase the same problem.
fn pit(singers: &mut Vec<(String, mpsc::Sender<String>)>) {
use rand::Rng;
let mut rng = rand::thread_rng();
let i1 = rng.gen_range(0..singers.len());
let i2 = rng.gen_range(0..singers.len());
// This will add dunsel "singers" to the vector who will get
// pitted against one another. The actual code makes sure that
// there are at least 2 singers in queue. What is does not do -
// and neither should it - is check if they are dummy objects.
// Rust did not like me using singers[i1].take().unwrap() and
// complained about iterators not being implemented for Sender?
let (dunsel, _) = mpsc::channel::<String>(1);
let s1 = std::mem::replace(&mut singers[i1], (String::new(), dunsel.clone()));
let s2 = std::mem::replace(&mut singers[i2], (String::new(), dunsel.clone()));
// returns s1, s2... not needed for MRE
}
let mut v = vec![];
let (tx, _) = mpsc::channel::<String>(256); // receiver is not needed for MRE
for name in vec!["name1".to_string(), "name2".to_string(), "name3".to_string()] {
// In the actual code, the singer clients are sent this tx
// and they send their transmitter channels via this tx, which
// is then pushed to the vector. Here, it just accepts `String`s
// So, tx is of the type mpsc::Sender<mpsc::Sender<String>>!!
v.push((name.clone(), tx.clone()));
}
tokio::spawn(async move {
let mut v = v;
pit(&mut v);
});
}
