// secret key, temporary credentials become invalid if
	// server admin credentials change. This is done to ensure
	// that clients cannot decode the token using the temp
	// secret keys and generate an entirely new claim by essentially
	// hijacking the policies. We need to make sure that this is
	// based on admin credential such that token cannot be decoded
	// on the client side and is treated like an opaque value.

	if !b.set {
		return nil
	}
	return e.EncodeElement(b.val, startElement)
}

// UnmarshalXML decodes delete marker boolean from the XML form.
func (b *Boolean) UnmarshalXML(d *xml.Decoder, startElement xml.StartElement) error {
	var exp bool
	err := d.DecodeElement(&exp, &startElement)
	if err != nil {
		return err
	}
	b.val = exp
	b.set = true

}

// IsEmpty - returns whether reader args is empty or not.
func (args *ReaderArgs) IsEmpty() bool {
	return !args.unmarshaled
}

// UnmarshalXML - decodes XML data.
func (args *ReaderArgs) UnmarshalXML(d *xml.Decoder, start xml.StartElement) (err error) {
	args.FileHeaderInfo = none
	args.RecordDelimiter = defaultRecordDelimiter
	args.FieldDelimiter = defaultFieldDelimiter

we can choose to extract and act only the objects within the top-level array:
```go
f, _ := os.Open("input.json")
decoder := jstream.NewDecoder(f, 1) // extract JSON values at a depth level of 1
for mv := range decoder.Stream() {
  fmt.Printf("%v\n ", mv.Value)
}
```

output:
```
map[desc:RGB colors:[red green blue]]
map[desc:CMYK colors:[cyan magenta yellow black]]
```

		// same. 'volume not found' usually means its a fresh disk.
		if errors.Is(err, errFileNotFound) || errors.Is(err, errVolumeNotFound) {
			return nil, errUnformattedDisk
		}
		return nil, err
	}

	// Try to decode format json into formatConfigV1 struct.
	format = &formatErasureV3{}
	if err = json.Unmarshal(data, format); err != nil {
		return nil, err
	}

	if heal {

	if !t.set {
		return nil
	}
	type transitionWrapper Transition
	return enc.EncodeElement(transitionWrapper(t), start)
}

// UnmarshalXML decodes transition field from the XML form.
func (t *Transition) UnmarshalXML(d *xml.Decoder, startElement xml.StartElement) error {
	type transitionWrapper Transition
	var trw transitionWrapper
	err := d.DecodeElement(&trw, &startElement)
	if err != nil {

}

// MarshalXML - encodes to XML data.
func (arn ARN) MarshalXML(e *xml.Encoder, start xml.StartElement) error {
	return e.EncodeElement(arn.String(), start)
}

// UnmarshalXML - decodes XML data.
func (arn *ARN) UnmarshalXML(d *xml.Decoder, start xml.StartElement) error {
	var s string
	if err := d.DecodeElement(&s, &start); err != nil {
		return err
	}

	parsedARN, err := parseARN(s)
	if err != nil {
		return err
	}

	if (s == SourceSelectionCriteria{}) {
		return nil
	}
	if !s.IsValid() {
		return errInvalidSourceSelectionCriteria
	}
	return nil
}

// UnmarshalXML - decodes XML data.
func (s *SourceSelectionCriteria) UnmarshalXML(dec *xml.Decoder, start xml.StartElement) (err error) {
	// Make subtype to avoid recursive UnmarshalXML().
	type sourceSelectionCriteria SourceSelectionCriteria
	ssc := sourceSelectionCriteria{}

// UnmarshalYAML - BatchJobExpirePurge extends unmarshal to extract line, col
func (p *BatchJobExpirePurge) UnmarshalYAML(val *yaml.Node) error {
	type purge BatchJobExpirePurge
	var tmp purge
	err := val.Decode(&tmp)
	if err != nil {
		return err
	}

	*p = BatchJobExpirePurge(tmp)
	p.line, p.col = val.Line, val.Column
	return nil
}

// Validate returns nil if value is valid, ie > 0.

	return fmt.Errorf("%w (offline-disks=%d/%d)", writeErr, countErrs(p.errs, errDiskNotFound), len(p.writers))
}

// Encode reads from the reader, erasure-encodes the data and writes to the writers.
func (e *Erasure) Encode(ctx context.Context, src io.Reader, writers []io.Writer, buf []byte, quorum int) (total int64, err error) {
	writer := &multiWriter{
		writers:     writers,
		writeQuorum: quorum,