<?php

/**
 * @param class-string<SimpleXMLElement> $class_name
 * @return SimpleXMLElement|false
 */
function simplexml_load_file(string $filename, ?string $class_name = SimpleXMLElement::class, int $options = 0, string $namespace_or_prefix = '', bool $is_prefix = false) {}

/**
 * @param class-string<SimpleXMLElement> $class_name
 * @return SimpleXMLElement|false
 */
function simplexml_load_string(string $data, ?string $class_name = 'SimpleXMLElement', int $options = 0, string $namespace_or_prefix = '', bool $is_prefix = false) {}

/**
 * @param class-string<SimpleXMLElement> $class_name
 */
function simplexml_import_dom(DOMNode $node, ?string $class_name = 'SimpleXMLElement'): ?SimpleXMLElement {}

/**
 * @param class-string<SimpleXMLElement> $class_name
 * @php-from 8.1
 */
function simplexml_import_dom(SimpleXMLElement|DOMNode $node, ?string $class_name = 'SimpleXMLElement'): ?SimpleXMLElement {}

/**
 * @implements Traversable<string, SimpleXMLElement>
 * @psalm-no-seal-properties
 */
class SimpleXMLElement implements Traversable, Countable
{
    /** @return array<array-key, SimpleXMLElement>|null|false */
    public function xpath(string $expression) {}

    public function registerXPathNamespace(string $prefix, string $namespace): bool {}

    /** @return ($filename is null ? string|false : bool) */
    public function asXML(?string $filename = null) {}

    /**
     * @return ($filename is null ? string|false : bool)
     * @alias SimpleXMLElement::asXML
     */
    public function saveXML(?string $filename = null) {}

    public function getNamespaces(bool $recursive = false): array {}

    /** @return array|false */
    public function getDocNamespaces(bool $recursive = false, bool $fromRoot = true) {}

    public function children(?string $namespaceOrPrefix = null, bool $isPrefix = false): ?SimpleXMLElement {}

    public function attributes(?string $namespaceOrPrefix = null, bool $isPrefix = false): ?SimpleXMLElement {}

    final public function __construct(string $data, int $options = 0, bool $dataIsURL = false, string $namespaceOrPrefix = '', bool $isPrefix = false) {}

    /** @psalm-ignore-nullable-return */
    public function addChild(string $qualifiedName, ?string $value = null, ?string $namespace = null): ?SimpleXMLElement {}

    public function addAttribute(string $qualifiedName, string $value, ?string $namespace = null): void {}

    public function getName(): string {}

    public function __toString(): string {}

    public function count(): int {}

    public function __get(string $name): SimpleXMLElement|SimpleXMLIterator|null {}

    public function __set(string $name, $value): void {}
}

/**
 * @implements RecursiveIterator<string, SimpleXMLElement>
 */
class SimpleXMLIterator extends SimpleXMLElement implements RecursiveIterator, Countable
{
    public function count(): int {}

    public function rewind(): void {}

    public function valid(): bool {}

    public function current(): SimpleXMLIterator {}

    public function key(): ?string {}

    public function next(): void {}

    public function hasChildren(): bool {}

    public function getChildren(): SimpleXMLIterator {}
}

/**
 * @implements RecursiveIterator<string, SimpleXMLElement>
 * @php-from 8.0
 */
class SimpleXMLElement implements Stringable, Countable, RecursiveIterator
{
    public function count(): int {}

    public function rewind(): void {}

    public function valid(): bool {}

    public function current(): SimpleXMLElement {}

    public function key(): ?string {}

    public function next(): void {}

    public function hasChildren(): bool {}

    public function getChildren(): ?SimpleXMLElement {}
}

/** @php-from 8.0 */
class SimpleXMLIterator extends SimpleXMLElement
{
    public function current(): SimpleXMLElement {}

    public function getChildren(): ?SimpleXMLElement {}
}