CHAPTER 7

Functions and Lists

Functions in Zig are comparable to mathematical functions: we pass in some input parameters and return a value using return <returned-value>. To define a function, we use this form:

fn name ( param: type, … , paramN: typeN ) return_type{

// … function code

return value;

// if the return type is void, we don’t return anything

};

It is mandatory to specify the return type, even if it is void (nothing). The value returned by a function must match the type indicated in its declaration. Returning nothing (not writing return) is the same as returning nothing with return;

It is like pouring an empty ladle:

void_ladle.zig

const std = @import("std");

const print = std.debug.print;

fn empty() void {}

fn nothing() void {

return;

}

pub fn main() void {

const void_x = empty();

const void_y = nothing();

print("Returned empty:{} , nothing:{}\n", .{

void_x, void_y });

}

$ zig run voidfun.zig

Returned empty:void , nothing:void