Async/Await implementation in Go with generics for better IDE support

async.go

package async

// This snippet is an update on what we see in
// https://hackernoon.com/asyncawait-in-golang-an-introductory-guide-ol1e34sg

// Also this one follows this assumptions from this article: https://appliedgo.net/futures/
// Assumption #1: It is ok that the spawned goroutine blocks after having calculated the result.
// Assumption #2: The reader reads the result only once.
// Assumption #3: The spawned goroutine provides a result within a reasonable time.

import "context"

type future[K any] struct {
	await func(ctx context.Context) K
}

type Fiber[K any] interface {
	Await() K
	AwaitWithContext(ctx context.Context) K
}

func (f future[K]) Await() K {
	return f.await(context.Background())
}

func (f future[K]) AwaitWithContext(ctx context.Context) K {
	return f.await(ctx)
}

func Future[K any, F func() K](f F) Fiber[K] {
	var r K
	ch := make(chan struct{})
	go func() {
		defer close(ch)
		r = f()
	}()
	return future[K]{
		await: func(ctx context.Context) K {
			select {
			case <-ch:
				return r
			case <-ctx.Done():
				return r
			}
		},
	}
}

/// main.go

package main

import (
	"fmt"
	"main/async"
	"time"
)

func DoneAsync() int {
	fmt.Println("Warming up ...")
	time.Sleep(3 * time.Second)
	fmt.Println("Done ...")
	return 1
}

func main() {
	fmt.Println("Let's start ...")
	future := async.Future(DoneAsync)
	fmt.Println("Done is running ...")
	val := future.Await()
	fmt.Println(val)
}

Here is IDE support!