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//
// The real power of async shows when you launch MULTIPLE tasks!
//
// With io.async(), you can start several operations, then await
// them all. The Io backend may run them concurrently:
//
// var f1 = io.async(taskA, .{});
// defer _ = f1.cancel(io);
// var f2 = io.async(taskB, .{});
// defer _ = f2.cancel(io);
// const a = f1.await(io);
// const b = f2.await(io);
//
// Notice the defer pattern: each async call is immediately
// followed by a defer cancel. This ensures cleanup even if
// we return early or hit an error before reaching await.
// Since await/cancel are idempotent, the defer is harmless
// if we've already awaited.
//
// Fix this program to launch both tasks and collect their results.
//
const std = @import("std");
const print = std.debug.print;
pub fn main(init: std.process.Init) !void {
const io = init.io;
// Launch both tasks asynchronously.
var future_a = io.async(slowAdd, .{ 1, 2 });
defer _ = future_a.cancel(io);
var future_b = ???(slowMul, .{ 6, 7 });
defer _ = future_b.cancel(io);
// Await both results.
const sum = future_a.await(io);
const product = future_b.await(io);
print("{} + {} = {}\n", .{ 1, 2, sum });
print("{} * {} = {}\n", .{ 6, 7, product });
print("Total: {}\n", .{sum + product});
}
fn slowAdd(a: u32, b: u32) u32 {
return a + b;
}
fn slowMul(a: u32, b: u32) u32 {
return a * b;
}
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