Golang Snippets

channeling.go

package main

import (
	"fmt"
	"sync"
	"time"
)

type message struct {
	data int
	wg   *sync.WaitGroup
}

func main() {
	var wg sync.WaitGroup
	c := make(chan message)
	go process(c)

	for i := 1; i < 6; i++ {
		fmt.Printf("S -> %d\n", i)
		wg.Add(1)
		c <- message{i, &wg}
		time.Sleep(time.Millisecond * 500)
	}

	wg.Wait()
	fmt.Println("Processing done.")
}

func process(c chan message) {
	for {
		msg := <-c
		printer(&msg)
	}
}

func printer(m *message) {
	defer m.wg.Done()
	fmt.Println("ping")
	time.Sleep(time.Second * 2)
	fmt.Printf("G <- %d\n", m.data)
}

io-writer.go

package main

import (
	"bytes"
	"fmt"
	"io"
)

func main() {
	me := person{
		Name:  "Axel",
		Age:   35,
		Admin: true,
	}

	var b bytes.Buffer

	me.Write(&b)

	fmt.Printf("%s", b.String())
}

type person struct {
	Name  string
	Age   int
	Admin bool
}

func (p *person) Write(w io.Writer) {
	out := fmt.Sprintf("%+v\t%+v\t%+v\n",
		p.Name, p.Age, p.Admin)
	w.Write([]byte(out))
}