Example

Example.go

package main

import (
 "errors"
 "fmt"
 "log"
)

var (
 errOne = errors.New("error one")
 errTwo = errors.New("error two")
)

func main() {
 fmtErrs := fmt.Errorf("error: %w, %w", errOne, errTwo)
 joinErrs := errors.Join(errOne, errTwo)

 log.Println(errors.Unwrap(joinErrs))
 log.Println(errors.Unwrap(fmtErrs))
 j, jok := joinErrs.(interface{ Unwrap() []error })
 f, fok := fmtErrs.(interface{ Unwrap() []error })
 log.Println(j.Unwrap(), jok)
 log.Println(f.Unwrap(), fok)
}