A small PHP userland enum replacement for SplEnum (spl_types)

Company.php

<?php

namespace SomeDomain;

use Ctors\Enum;

class Company extends Enum
{
    public const GOOGLE = 'Google';
    public const TWITTER = 'Twitter';
    public const FACEBOOK = 'Facebook';
    
    // Optional: default value
    public function __construct($value = null)
    {
        parent::__construct($value ?? self::GOOGLE);
    }

    // Optional: factory methods
    public function GOOGLE(): self
    {
        return new self(self::GOOGLE);
    }
}

Enum.php

<?php

namespace Ctors;

abstract class Enum
{
    protected string $value;
    
    public function __construct(string $value)
    {
        $classConstants = (new \ReflectionClass(static::class))->getConstants();

        if ('' === $value) {
            throw new \LogicException('Emum can\'t have a blank value');
        }

        if (! \in_array($value, array_values($classConstants), false)) {
            throw new \LogicException('Value not a const in enum '.static::class);
        }
        
        $this->value = $value;
    }
    
    public function __toString()
    {
        return (string) $this->value;
    }
    
    // Optional: if you need to list all possible values
    public function allValues(): array
    {
        return (new \ReflectionClass(static::class))->getConstants();
    }
}