package chain

import (
	"encoding/hex"
	"errors"
	"fmt"
)

func hexDecode(s string) ([]byte, error) {
	b, err := hex.DecodeString(s)
	if err != nil {
		return nil, err
	}
	if len(b) == 0 {
		return nil, errors.New("empty hex")
	}
	return b, nil
}

var _ = fmt.Sprintf