prog/web-servers.go

package main

import (
	"fmt"
	"net/http"
)

type Hello struct{}

func (h Hello) ServeHTTP(
	w http.ResponseWriter,
	r *http.Request) {
	fmt.Fprint(w, "Hello!")
}

func main() {
	var h Hello
	http.ListenAndServe("localhost:4000", h)
}