Cheating PHP integers

Question

This is in relation to my post here but taken in a completely different direction Charset detection in PHP

essentially, i\'m looking to reduce the memory that many h

Answer 1

Don't tell nobody!

class IntegerstringArray IMPLEMENTS ArrayAccess {

    var $evil = "0000111122220000ffff";

                 // 16 bit each


    function offsetExists ( $offset ) {
        return (strlen($this->evil) / 4) - 1 >= $offset;
    }

    function offsetGet ( $offset ) {
        return hexdec(substr($this->evil, $offset * 4, 4));
    }

    function offsetSet ( $offset , $value ) {

        $hex = dechex($value);
        if ($fill = 4 - strlen($hex)) {
            $hex = str_repeat("0",  $fill) . $hex;
        }

        for ($i=0; $i<4; $i++) {
            $this->evil[$offset*4+$i] = $hex[$i];
        }
    }

    function offsetUnset ( $offset ) {
        assert(false);
    }

}

So you can pretty much create an array object from this:

$array = new IntegerstringArray();
$array[2] = 65535;
print $array[2];

It internally stores a list and accepts 16-bit integers. The array offsets must be consecutive.

Not tested. Just as an implementation guide.