Таким чином його схема з'явиться в інтерфейсі користувача документації API:

<img src="/img/tutorial/dataclasses/image01.png">

## Dataclasses у вкладених структурах даних { #dataclasses-in-nested-data-structures }

Можна поєднувати `dataclasses` з іншими анотаціями типів, щоб створювати вкладені структури даних.

        // getMessage() may return null when constructed with null
        // This is expected behavior for exceptions with null cause
    }

    @Test
    public void test_nestedCause() {
        // Test with nested exceptions
        RuntimeException rootCause = new RuntimeException("Root cause");
        ParseException parseException = new ParseException("Parse error");
        parseException.initCause(rootCause);

        assertEquals(0, SessionSetupHandler.class.getDeclaredFields().length, "No fields expected");
        assertEquals(0, SessionSetupHandler.class.getDeclaredClasses().length, "No nested types expected");
    }

    @ParameterizedTest(name = "Implementation is instance: {0}")
    @MethodSource("implementations")
    @DisplayName("Happy path: can create implementations and use type checks")

// Copyright 2016 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.

// This file encapsulates some of the odd characteristics of the
// s390x instruction set, to minimize its interaction
// with the core of the assembler.

package arch

import (
	"cmd/internal/obj/s390x"
)

func jumpS390x(word string) bool {
	switch word {
	case "BRC",

# Copyright 2023 The TensorFlow Authors. All Rights Reserved.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,

        assertNotNull(exception);
        assertTrue(exception instanceof java.io.Serializable);
    }

    @Test
    public void test_nestedExceptions() {
        // Test nested exception handling
        Exception innerCause = new IllegalArgumentException("Invalid parameter");
        RuntimeException middleCause = new RuntimeException("Processing failed", innerCause);

            final int domainIdPointer = pacStream.readInt();

            // Skip some reserved fields
            pacStream.skipBytes(8);

            this.userAccountControl = pacStream.readInt();

            // Skip some reserved fields
            pacStream.skipBytes(28);

            // Extra SIDs information
            final int extraSidCount = pacStream.readInt();

    }

    @Test
    public void testCaseInsensitivity() throws Exception {
        // Windows reserved names should be caught regardless of case
        try {
            validator.validatePath("\\share\\con");
            fail("Should block lowercase reserved name");
        } catch (SmbException e) {
            // Expected
        }

        try {

        assertEquals(longMessage, exception.getMessage());
        assertNull(exception.getCause());
    }

    @Test
    public void test_constructor_withNestedCause() {
        // Test constructor with nested exception causes
        Exception rootCause = new IllegalStateException("Root cause");
        Exception middleCause = new RuntimeException("Middle cause", rootCause);
        String message = "Top level dictionary error";

Just functions that look the same as the *path operation functions*.

But still, it is very powerful, and allows you to declare arbitrarily deeply nested dependency "graphs" (trees).

/// tip

All this might not seem as useful with these simple examples.

But you will see how useful it is in the chapters about **security**.