Package http serves HTTP requests using any value that implementshttp.Handler:

package httptype Handler interface {    ServeHTTP(w ResponseWriter, r *Request)}

In this example, the type Hello implements http.Handler.

Visit http://localhost:4000/ to see the greeting.

Note: This example won‘t run through the web-based tour user interface. To try writing web servers you may want to Install 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)}

A Tour of Go Web servers