How do i solve this issue, can't explain the issue properly

[rishadbaniya]

How do i solve this issue..

Like, why??? why does it say dropped, when in fact i was gonna just await, how does it even make sense

[alice]

Don't post pictures of code.

[rishadbaniya]

it had me so overwhelming that i couldn't explain my problem, i couldn't even figure out the correct words for the issue here properly, that's why just to give more context what is going on i posted a picture

[alice]

If you refuse to put the code and full error message in a format where I can copy-paste it into e.g. an editor, then I wont help you.

[rishadbaniya]

error[E0716]: temporary value dropped while borrowed
   --> src/work/peer.rs:146:15
    |
146 |         match peer.borrow_mut().try_connect().await {
    |               ^^^^^^^^^^^^^^^^^
    |               |
    |               creates a temporary which is freed while still in use
    |               a temporary with access to the borrow is created here ...
...
183 |         };
    |          -
    |          |
    |          temporary value is freed at the end of this statement
    |          ... and the borrow might be used here, when that temporary is dropped and runs the destructor for type `RefMut<'_, Peer<'_>>`
    |
    = note: consider using a `let` binding to create a longer lived value

I couldn't even understand how the value is going to be dropped here

[alice]

Code blocks please:

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[rishadbaniya]

Sorry😓

[alice]

Looking at your code, it seems like you should just remove the RefCell entirely.

[rishadbaniya]

I could make it workable without using RefCell, but i somehow want to use the peer instance inside that match block to get one of the field's value

let PIECE_LENGTH = details.lock().await.piece_length.unwrap() as u32;

   loop {
       let mut peer = Peer::new(socket_adr, details.clone());

       match peer.try_connect().await {
           Some(((mut tcp_sender, mut tcp_receiver), channel_sender)) => {
               let y = peer.status.clone();
               // Continuosly reads on the stream for some message
               let read = async move {
                   loop {

but it shows me this error now,

error[E0502]: cannot borrow `peer.status` as immutable because it is also borrowed as mutable
   --> src/work/peer.rs:148:25
    |
146 |         match peer.try_connect().await {
    |               ------------------ mutable borrow occurs here
147 |             Some(((mut tcp_sender, mut tcp_receiver), channel_sender)) => {
148 |                 let y = peer.status.clone();
    |                         ^^^^^^^^^^^^^^^^^^^
    |                         |
    |                         immutable borrow occurs here
    |                         mutable borrow later used here

For more information about this error, try `rustc --explain E0502`. 

How do i edit the code in such a way that i can use the peer inside of that match block as well.

I understand here that i borrowed mutably, is there any way to drop that mutable borrow so that i can borrow it mutably again inside of that match block

[alice]

When it comes to RefCell, you generally can't use it in async code.

What does try_connect return?

[rishadbaniya]

It's weird! somehow pasting from my clipboard isn't working right now, but i've shown the return type in the second picture i sent

[alice]

Why does it return something with a lifetime on it?

[rishadbaniya]

It basically returns a wrapper around "ReadHalf" and "WriteHalf" of tokio

TcpStream in tokio::net - Rust

WriteHalf in tokio::net::tcp - Rust

[alice]

Why are you not using into_split?

[alice]

If you return a mutable reference from the function (there's a mutable reference inside those split halves), then you wont be able to access the value until you stop using that mutable reference.

[rishadbaniya]

oh shit..just checked out..never saw that actually....thanks! i just found out about it tbh

[rishadbaniya]

Can i ask you one simple question, i'm sort of immature in rust. How long does it usually take to be someone at your caliber?

[alice]

I believe people out there say that it took them a few months to be really comfortable with Rust.

As for me, I don't think people should try to compare themselves with me — I know Rust far more deeply than you need to to be productive with Rust.