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?
Could you not have a hashmap keyed on matches pointing to vectors of strings for the players in each match? Basically modeling the data how you want rather than relying on indexing.
Not sure I understand. What I’m trying to do is something like this:
So what I have as a key is a player name (AP username) and from that I need to find which match they’re in.
There’s nothing semantically useful about a match ID.
If you instead made your
lobbyfield aHashMap<String, MatchId>, then whenever you get an event from a known player, you can lookup the match they are in from the lobby map and use that to lookup other data about the match (such as the other players) via thematchesfield (assuming that was also changed to be a hashmap as described in my previous comment).