package main

import (
	"errors"
	"fmt"
)

type SentinelError string

func (s SentinelError) Error() string {
	return string(s)
}

func (s SentinelError) Is(target error) bool {
	return s.Error() == target.Error()
}

const (
	ErrId   = SentinelError("Wrong ID")
	ErrTest = SentinelError("Wrong Test")
)

func main() {
	errId := ErrId
	errTest := ErrTest
	fmt.Printf("Does ErrId found: %b\n", errors.Is(errId, ErrId))

	fmt.Printf("Does ErrTest found: %b\n", errors.Is(errId, ErrTest))

	fmt.Printf("Does ErrId found: %b\n", errors.Is(errTest, ErrId))

	fmt.Printf("Does ErrTest found: %b\n", errors.Is(errTest, ErrTest))
}