関数：引数と返り値

sample.go

package main

import (
  "fmt"
  "time"
)

func main() {
  logMessage( "STARTED" )
  time.Sleep( 1000 * time.Millisecond )
  logMessage( "SLEEPED" )
  time.Sleep( 1000 * time.Millisecond )
  logMessage( "FINISHED" )
}

func logMessage( message string ) {
  fmt.Println( buildMessage( message ) )
}

func getTime() string {
  return time.Now().String()
}

func getSeverity() string {
  return "INFO"
}

func buildMessage( message string ) ( tm, svr, msg string ) {
  tm  = getTime()
  svr = getSeverity()
  msg = ": " + message
  return
}