debounce.go

package main

import (
	"context"
	"fmt"
	"time"
)

func handle(ctx context.Context, name string) {
	for {
		select {
		case <-ctx.Done():
			return
		case <-time.After(time.Second * 3):
			fmt.Println("hello", name)
			return
		}
	}
}

func main() {
	var name string
	var cancel context.CancelFunc

	for {
		fmt.Println("input your name:")
		fmt.Scanln(&name)
    // cancel the previous goroutine when we receive new input
		if cancel != nil {
			cancel()
		}

		var ctx context.Context
		ctx, cancel = context.WithCancel(context.Background())
		go handle(ctx, name)
	}
}