A simpler enumish class

enumish.php

<?php

abstract class Pais {
    const ARGENTINA = 'Argentina';
    const URUGUAY = 'Uruguay';

    static private $values = [];

    static function init() {
        $refle = new ReflectionClass(__CLASS__);
        foreach ($refle->getConstants() as $symbol => $con) {
            echo "encontre una constante: $symbol -> $con\n";
            self::$values[$con] = new $con;
        }
    }

    static function get($symbol) {
        return self::$values[$symbol];
    }

    abstract function getUrl();

    function __toString() {
        return get_called_class();
    }
}

class Argentina extends Pais {
    function getUrl() { return 'AAA'; }
}
class Uruguay extends Pais {
    function getUrl() { return 'UUU'; }
}

Pais::init();

echo "ar constant: " . Pais::ARGENTINA . PHP_EOL;
echo "ar object  : " . Pais::get(Pais::ARGENTINA) . PHP_EOL;
echo "ar url     : " . Pais::get(Pais::ARGENTINA)->getUrl() . PHP_EOL;
echo "uy constant: " . Pais::URUGUAY . PHP_EOL;
echo "uy object  : " . Pais::get(Pais::URUGUAY) . PHP_EOL;
echo "uy url     : " . Pais::get(Pais::URUGUAY)->getUrl() . PHP_EOL;