gistfile1.go

package main

import (
  "fmt"
  "time"
  "errors"
)

func run() (str string, err error) {
  time := time.Now()
  str = ""
  err = nil
  
  if time.Minute() < 30 {
    err = errors.New("Error[TimeError]: You're under 30 minutes!")
  } else {
    str = "Past 30 minutes!"
  }
  return 
}

func main() {
  str, err := run()
  if err != nil {
    fmt.Println(err)
  } else {
    fmt.Println(str)
  }
}