Functions

Basic Functions

Define functions with fn:

fn greet() {
    say("Hello, world!");
}

Call a function by name:

greet();

Parameters

Functions can take parameters with type annotations:

fn heal(target: selector, amount: int) {
    effect(target, "instant_health", amount, 1);
    say("Healed!");
}

heal(@a, 2);

Return Types

Specify return types with ->:

fn double(x: int) -> int {
    return x * 2;
}

let result: int = double(5); // 10

Default Arguments

Parameters can have default values:

fn spawn_mob(mob: string, count: int = 1) {
    repeat(count) {
        summon(mob);
    }
}

spawn_mob("zombie");       // spawns 1 zombie
spawn_mob("skeleton", 5);  // spawns 5 skeletons

Multiple Parameters

fn setup_team(team_name: string, color: string, friendly_fire: bool = false) {
    team_add(team_name);
    team_modify(team_name, "color", color);
    if (!friendly_fire) {
        team_modify(team_name, "friendlyFire", "false");
    }
}

setup_team("red", "red");
setup_team("blue", "blue", true);

Calling Functions

Functions compile to .mcfunction files. They can be called:

• From other functions
• Automatically via decorators like @tick and @load
• As command targets in-game via /function namespace:function_name

@load
fn init() {
    setup_team("red", "red");
    setup_team("blue", "blue");
    say("Teams ready!");
}

Next Steps

• Decorators — Trigger functions automatically
• Lambdas — Inline function expressions