__wakeup

[imme-emosol]

In https://github.com/chrisnharvey/PHP-Singleton-Trait/blob/master/Singleton.php __wakeup is also used in the pattern.

So, __wakeup should be added, or
text should be added to the readme explaining why __wakeup is not there.

[byjg]

The magic function __sleep and __wakeup is only for customize serialization and unserialization (here). I don't think so if it is necessary.

The example you send to me it seems the class cannot be serialized.

class Test
{
        public $a = 10;

        public function __wakeup() {}

        public function __sleep() {}

}

$test = new Test();

print_r(serialize($test));

throws the error: serialize(): __sleep should return an array only containing the names of instance-variables to serialize what is expected by the documentation.

So, today I can serialize the singleton class. The wakeup/sleep will only necessary if we do not want to permit serialize; I made an example that the serialization works:

<?php
require "vendor/autoload.php";

class Example
{
    // You need to use the trait here
    use \ByJG\DesignPattern\Singleton;

    public $variable;
    // Put your code below
}

$example = Example::getInstance();
$example->variable = 30;

$serializedExample = serialize($example);
$newExample = unserialize($serializedExample);

print_r($newExample->variable);

echo "\n";

[imme-emosol]

Thanks for the elaborate answer, with investigation and examples.
So, what do you think about de-/unserializing multiple times .., e.g.: $newExample = unserialize($serializedExample); $newExample2 = unserialize($serializedExample);

[byjg]

OK. I got your point now. It worked like a charm as a language, but the Singleton concept by the book has only one instance of the class. If I unserializing multiple times I brake this concept.

So, your suggestion is to avoid this. I'll do it.

[byjg]

Done.

[imme-emosol]

very nice :)