What I'd like ti achieve is that when I call $obj->CAT[15]; the $obj would check if the property CAT exists if not, get the value on the fly
public function __get($var){
if($var == "CAT") return $this->cats->get_cat($cat_id);
}
so my question is... how to get array's value 15 from my example? to pass it to my get_cat method?
Have __get return an instance of ArrayAccess which will delegate to get_cat in its offsetGet method.
Something like this:
class CachedCategories implements ArrayAccess
{
private $memcachedClient;
public function __construct($memcachedClient)
{
$this->memcachedClient = $memcachedClient;
}
// Called when using `$cats[18] = "foo"`
public function offsetSet($key, $value)
{
$this->memcachedClient->set($key, $value);
}
// Called when using `$cat = $cats[18]`
public function offsetGet($key)
{
return $this->memcachedClient->get($key);
}
// Called when using `isset($cats[18])`
public function offsetExists($key)
{
return $this->memcachedClient->get($key) !== false;
}
// Called when using `unset($cats)`
public function offsetUnset($key)
{
$this->memcachedClient->delete($key);
}
}
$cats = new CachedCategories($someMemcachedClient);
$cats[18];
get_cart function as suggested by GolezTrol. But if you need to use __get you can try this one.
class Test
{
protected $cats;
function __construct()
{
$this->cats = new ArrayObject(); // or your own implementation
$this->cats[33] = "hey";
}
public function __get($name)
{
if($name == "CAT") return $this->cats;
}
}
$a = new Test();
echo $a->CAT[33];
see http://www.php.net/ArrayAccess to implement your own list/map
hope this helps!
If I understood correctly what you want to achieve, you could use a closure:
class kittengarten
{
var $cats;
function __construct()
{
$this->cats[0]='Jerry';
$this->cats[1]='John';
$this->cats[2]='Barack';
}
public function __get($var)
{
if($var == "CAT")
{
$array_of_cats=$this->cats;
return function($num) use ($array_of_cats)
{
return $array_of_cats[$num];
};
}
}
}
$kittengarten=new kittengarten();
echo 'The third directly accessed cat is '.$kittengarten->cats[2];
$cat=$kittengarten->CAT;
if (is_string($cat)) echo $kittengarten->CAT;
else echo 'The third cat accessed using closure is '.$cat(2);
Output:
The third directly accessed cat is Barack
The third cat accessed using closure is Barack
$cat_idsince it will be provided, after__getreturned a value$obj->CAT[15]will be valid syntax. See the complete list of changes. Also check out this nice overview of new features$obj->CAT[15]is already valid syntax. The new array dereferencing stuff covers array-like values returned from functions, like:foo()[0].