<?php

declare(strict_types=1);

final class Foo
{
    private string $string;

    public function __get(string $propertyName): void
    {
        throw new \Exception('Class property which was unset earlier is now passed to __get');
    }

    public function setString(string $string): void
    {
        $this->string = $string;
    }

    public function string(): string
    {
        return $this->string;
    }

    public function unsetString(): void
    {
        unset($this->string);
    }
}

$foo = new Foo();

try {
    echo $foo->string() . PHP_EOL;
} catch (\Throwable $throwable) {
    echo $throwable->getMessage() . PHP_EOL;
}

$foo->setString('test');

echo $foo->string() . PHP_EOL;

$foo->unsetString();

try {
    echo $foo->string() . PHP_EOL;
} catch (\Throwable $throwable) {
    echo $throwable->getMessage() . PHP_EOL;
}