modulus

I have a struct that looks like this:

pub struct Game {
    /// A HashSet with the players waiting to play as account strings.
    lobby: HashSet<String>,
    /// capacity determines  how many people a match contains.
    capacity: u8,
    /// A vector of ongoing matches.
    matches: Vec<Match>,
    /// HashSet indicating for each player which match they are in.
    players: HashMap<String, usize>,
}

I realised that this won't work because if there are 3 matches (0, 1, 2) and I remove 1 because it ends, the players that used to point at 2 will be pointing outside the vector or to an incorrect match.

So I thought the obvious solution was to use a reference to the match: players: HashMap<String, &Match>. But this makes lifetimes very complicated.

What's a good way to deal with a case like these where data are interrelated in the same struct?

Hi there,

I'm trying to do some native windows rust programming. I'm using native-windows-gui and native-windows-derive to do it, but if I try to mix that with tokio, I get the following:

No entry point found error for GetWindowSubclass. On console, I get:

error: process didn't exit successfully: `C:\source\myprojectanem\target\debug\myprojectname.exe` (exit code: 0xc0000139, STATUS_ENTRYPOINT_NOT_FOUND)

If I change

#[tokio::main]
async fn main() {

to:

fn main() {

The problem goes away, but obviously I can't use tokio then.

Any clue what the problem is and how to fix it?

Hi there,

I'm working on a bot to do social games on the fedi, and using the mastodon-async crate for communicating with the ActivityPub server in question. At the moment I'm using tokio mt as a runtime, though I'm new at async so if you think I shouldn't let me know.

The pattern I want to implement is the following:

• At any given time, a user sends a "play" message to the bot.
• If the player list is empty, the player is added to it awaiting someone else.
• Otherwise, the bot checks if there are enough players on its list (who have previously sent a play message). For some games, enough is 1, since it's a 2-player game, for some it's 3 or more.
• If there are enough players, play commences. list is cloned for that match, then emptied so other players can get in.

What I'm not very clear is how to keep this list to assure that sequence will be respected. I.a., if two play messages come reasonably quick together, I want one to be processed, then entered on the list, or get the match to start; then the other to get processed.

My current thoughts:

• I could use a channel that receives the player accounts. When a new player is added, it performs the logic.
• I could use a mutex with a list (or an option player value for the degenerate case of 2-player games).

Any thoughts on what the reasonable thing to do is here? I'm very new to async and while I realise there's probably lots of ways to do this, they're not all equally ergonomic and I want to avoid myself future pain.

Hi there,

First off thanks a lot for setting up a Lemmy instance! I know that sysadmin stuff can be very draining, especially with fiddly early-days software.

Just posting here to give you my support, and incidentally to try a little issue I've noticed with Lemmy, where paragraphs breaks don't appear properly for me with NVDA and Firefox. I didn't find multi-paragraph posts or comments, so I'm making one to test.

Once more, thanks, and cool to see you here!--so to speak.