Constrain type to generic struct

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Thanks for the prompt response! Duck typing does make sure my code is correct, but I was hoping for something that gives a better dev experience, “communicate intent precisely” is part of Zig’s zen after all.

After more searching I found this post which inspired me to try moving the functions into Player’s fields instead:

pub const Player = struct {
    drawAt: fn (x: u16, y: u16, char: u23) void,
    playSound: fn (sound: Sound) void,

    pub fn init(
        comptime drawAt: fn (x: u16, y: u16, char: u23) void,
        comptime playSound: fn (sound: Sound) void,
    ) @This() {
        return .{ .drawAt = drawAt, .playSound = playSound };
    }
    // More code...
};

pub const Match = struct {
    players: []Player,
    // Mode code...
};

As far as I can tell, once compiled it’s functionally equivalent to everything above and IMO conveys intent better (drawAt and playSound are injected dependencies, why should they be baked in at type declaration?).

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