Iterating through PHP class variables when SplEnum is involved - php

Question

I'm trying to iterate through the variables within a PHP class that contains an SplEnum. It doesn't work. Here's the code:
class enum extends SplEnum { const First = 1; }
class fruit
{
public $enum;
public $variable = 2;
public function __construct(enum $enum)
{
$this->enum = $enum;
}
}
$apple = new fruit(new enum(enum::First));
foreach ($apple as $key => $value) {
echo "[$key] => $value\n";
}
This is the output:
[enum] => 1
PHP Fatal error: Uncaught exception 'UnexpectedValueException' with message 'Value not a const in enum enum' in /home/test.php:16
Stack trace:
#0 /home/test.php(16): unknown()
#1 {main}
thrown in /home/test.php on line 16
It seems that what is happening is that the foreach loop is trying to turn each class variable into an enum. How do I correctly iterate through the variables in the class?

Answer 1

The SPL Lib is known to be a buggy one.
You can switch the order of the variable declaration to
public $variable = 2;
public $enum;
And the example will work.
It will also work if you delete the enum property declaration altogether.
class fruit
{
public $variable = 2;
public function __construct(enum $enum)
{
$this->enum = $enum;
}
}
Maybe your best bet is to avoid it, or keep it private/protected.