Что касается JavaScript (в браузере и NodeJS), раньше там использовали для этой цели
<abbr title="callback">"обратные вызовы"</abbr>. Что выливалось в
<a href="http://callbackhell.ru/" class="external-link" target="_blank">ад обратных вызовов</a>.

## Сопрограммы

			// If we are unable to parse them and the prefix field looks like
			// an ASCII string, then we fallback on the pre-Go1.8 behavior
			// of treating these fields as the USTAR prefix field.
			//
			// Note that this will not use the fallback logic for all possible
			// files generated by a pre-Go1.8 toolchain. If the generated file
			// happened to have a prefix field that parses as valid

        try ( SmbSessionImpl treesess = t.getSession() ) {
            if ( treesess.getCredentials().isAnonymous() || treesess.getCredentials().isGuest() ) {
                // refresh anonymous session or fallback to anonymous from guest login
                try ( SmbSessionInternal s = trans
                        .getSmbSession(this.ctx.withAnonymousCredentials(), treesess.getTargetHost(), treesess.getTargetDomain())

	if s3Select.progressReader != nil {
		return s3Select.progressReader.Stats()
	}

	return -1, -1
}

// Open - opens S3 object by using callback for SQL selection query.
// Currently CSV, JSON and Apache Parquet formats are supported.
func (s3Select *S3Select) Open(rsc io.ReadSeekCloser) error {
	offset, length, err := s3Select.ScanRange.StartLen()
	if err != nil {

	} {
		_, err = os.Stat(envfile)
		if err == nil {
			return true
		}
	}
	if osIsNotExist(err) {
		// if none of the files are present we may be running inside
		// CRI-O, Containerd etc..
		// Fallback to our container specific ENVs if they are set.
		return env.IsSet("MINIO_ACCESS_KEY_FILE")
	}

	// Log error, as we will not propagate it to caller
	internalLogIf(GlobalContext, err)

	return err == nil

		gorootPath = runtime.GOROOT()
		if gorootPath != "" {
			return
		}

		// runtime.GOROOT is empty — perhaps go_android_exec was built with
		// -trimpath and GOROOT is unset. Try 'go env GOROOT' as a fallback,
		// assuming that the 'go' command in $PATH is the correct one.

		cmd := exec.Command("go", "env", "GOROOT")
		cmd.Stderr = os.Stderr
		out, err := cmd.Output()
		if err != nil {

			}
			s += "}"
		}
		res = append(res, []byte(s)...)
	}
	res = append(res, '}')
	return res, nil
}

// files returns files as callback.
func (x xlMetaInlineData) files(fn func(name string, data []byte)) error {
	if len(x) == 0 {
		return nil
	}
	if !x.versionOK() {
		return errors.New("xlMetaInlineData: unknown version")
	}

	// If the request context is canceled, the stream will no longer process requests.
	Requests chan<- Req
}

// Results returns the results from the remote server one by one.
// If any error is returned by the callback, the stream will be canceled.
// If the context is canceled, the stream will be canceled.
func (s *TypedStream[Req, Resp]) Results(next func(resp Resp) error) (err error) {
	return s.responses.Results(func(b []byte) error {

            return packagedArtifactFile;
        }

        if (!hasBeenPackagedDuringThisSession(project)) {
            // fallback to loose class files only if artifacts haven't been packaged yet
            // and only for plain old jars. Not war files, not ear files, not anything else.

    frame.writeByte(99) // type 99
    frame.writeByte(FLAG_NONE)
    frame.writeInt(expectedStreamId)
    frame.writeInt(111111111) // custom data
    reader.nextFrame(requireSettings = false, BaseTestHandler()) // Should not callback.
  }

  @Test fun onlyOneLiteralHeadersFrame() {
    val sentHeaders = headerEntries("name", "value")
    val headerBytes = literalHeaders(sentHeaders)
    writeMedium(frame, headerBytes.size.toInt())