retry.go

package main

import (
	"fmt"
)

type Retryer func() (bool, error)

func Do(retryNumber uint32, fn Retryer) error {
	isRepeat := true
	err := (error)(nil)

	for retryNumber > 0 && isRepeat {
		isRepeat, err = fn()
		retryNumber--
	}

	return err
}

func main() {
	fmt.Print("hello world")
	a := 2
	Do(3, func() (bool, error) {
		fmt.Println("try")
		if a == 1 {
			return false, nil
		}
		return true, nil
	})
}