func Errorf(format string, a ...interface{}) error {
	e := fmt.Errorf(format, a...)
	ee := Error{}
	ee.msg = e.Error()
	ee.cause = errors.Unwrap(e)
	return ee
}

// Unwrap the internal error.
func (e Error) Unwrap() error { return e.cause }

// Error 'error' compatible method.
func (e Error) Error() string {
	if e.msg == "" {
		return "crypto: cause <nil>"
	}
	return e.msg
}

var (

type ChecksumMismatch struct {
	Want string
	Got  string
}

func (e ChecksumMismatch) Error() string {
	return "Bad checksum: Want " + e.Want + " does not match calculated " + e.Got
}

// IsChecksumMismatch matches if 'err' is hash.ChecksumMismatch
func IsChecksumMismatch(err error) bool {
	var herr ChecksumMismatch
	return errors.As(err, &herr)

	// ErrSubQueryRequired sub query required
	ErrSubQueryRequired = errors.New("sub query required")
	// ErrInvalidData unsupported data
	ErrInvalidData = errors.New("unsupported data")
	// ErrUnsupportedDriver unsupported driver
	ErrUnsupportedDriver = errors.New("unsupported driver")
	// ErrRegistered registered
	ErrRegistered = errors.New("registered")

package grid

import (
	"errors"
	"fmt"
)

var (
	// ErrUnknownHandler is returned when an unknown handler is requested.
	ErrUnknownHandler = errors.New("unknown mux handler")

	// ErrHandlerAlreadyExists is returned when a handler is already registered.
	ErrHandlerAlreadyExists = errors.New("mux handler already exists")

package nodeagent

import (
	"errors"
	"fmt"
)

var ErrPartialAdd = errors.New("partial add error")

type PartialAddError struct {
	inner error
}

func (e *PartialAddError) Error() string {
	return fmt.Sprintf("%s: %v", ErrPartialAdd.Error(), e.inner)
}

func (e *PartialAddError) Unwrap() []error {
	return []error{ErrPartialAdd, e.inner}
}

//
// You should have received a copy of the GNU Affero General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.

package config

// UI errors
var (
	ErrInvalidXLValue = newErrFn(
		"Invalid drive path",
		"Please provide a fresh drive for single drive MinIO setup",
		"MinIO only supports fresh drive paths",
	)

	ErrInvalidBrowserValue = newErrFn(

			<h2>
				<la:message key="labels.error_title" />
			</h2>
			<div>
				<la:info id="msg" message="true">
					<div class="alert alert-info">${msg}</div>
				</la:info>
				<la:errors styleClass="list-unstyled"/>
			</div>
		</div>
	</main>
	<jsp:include page="../footer.jsp" />
	<input type="hidden" id="contextPath" value="<%=request.getContextPath()%>" />
	<script type="text/javascript"

	if errors.Is(err, syscall.EADDRINUSE) {
		return ErrPortAlreadyInUse(err).Msg("Specified port is already in use")
	} else if errors.Is(err, syscall.EACCES) || errors.Is(err, syscall.EPERM) {
		if netErr, ok := err.(*net.OpError); ok {
			return ErrPortAccess(netErr).Msg("Insufficient permissions to use specified port")
		}
	}

	// Failed to identify what type of error this, return a simple UI error

// along with this program.  If not, see <http://www.gnu.org/licenses/>.

package kms

// Error encapsulates S3 API error response fields.
type Error struct {
	Err            error
	APICode        string
	HTTPStatusCode int
}

func (e Error) Error() string {
	return e.Err.Error()

```
1 validation error
path -> item_id
  value is not a valid integer (type=type_error.integer)
```

#### `RequestValidationError` или `ValidationError`

!!! warning "Внимание"
    Это технические детали, которые можно пропустить, если они не важны для вас сейчас.