the trait `Future` is not implemented for `Result<std::net::TcpListener, std::io::Error>

Question

I try to initialize a server in rust with async functionality using Tokio library:

use std::net::TcpListener;

#[tokio::main]
async fn main() {
    // let listener=TcpListener::bind("localhost:8080").await.unwrap();
    let listener = TcpListener::bind("127.0.0.1:8080").await.unwrap();
    let (socket,_addr)=listener.accept().await.unwrap();
}

This throws an error saying that:

 the trait `Future` is not implemented for `Result<std::net::TcpListener, std::io::Error>`

When I hover over listener its type is unknown.

Answer 1

You have:

use std::net::TcpListener;

And you probably want to have:

use tokio::net::TcpListener;

Here is an example from tokio's docs:

use tokio::net::TcpListener;

use std::io;

async fn process_socket<T>(socket: T) {
    // do work with socket here
}

#[tokio::main]
async fn main() -> io::Result<()> {
    let listener = TcpListener::bind("127.0.0.1:8080").await?;

    loop {
        let (socket, _) = listener.accept().await?;
        process_socket(socket).await;
    }
}