decorator_example.go

package main

import "fmt"

type Any interface{}
type Callback func(data Any)
type CallbackDecorator func(Callback) Callback

func Greetings(msg Any) {
    fmt.Print("Hello there ", msg) 
}

func DecorateWithSymbols(cb Callback) Callback {
    return func(data Any) {
        fmt.Print("!!!%%%&&& ")
        cb(data)
        fmt.Print(" &&&%%%!!!")
    }
}

func main() {
    greeter := DecorateWithSymbols(Greetings)
    greeter("Diego")
}