#30113 [Opn]: ArrayAccess interface does not implement count functionality
| From: | kevin at stormtide dot ca | Date: | Fri, 29 Oct 2004 16:25:24 +0000 |
| Subject: | #30113 [Opn]: ArrayAccess interface does not implement count functionality | ||
| References: | 1 | Groups: | php.pear.dev |
| Request: | Send a blank email to pear-dev+get-34152@lists.php.net to get a copy of this message | ||
ID: 30113
User updated by: kevin at stormtide dot ca
Reported By: kevin at stormtide dot ca
Status: Open
Bug Type: PECL related
Operating System: ANY
PHP Version: 5.0.1
New Comment:
Sorry for the mockup code. I thought it would be sufficient to describe
the problem.
Here is actually executable code.
<?PHP
error_reporting(E_ALL);
class NArray Implements ArrayAccess, Iterator {
private $arraylist;
private $currentIndex;
function __construct() {
$this->currentIndex = 0;
$this->arraylist = array();
}
function offsetExists($offset){
if(isset($this->arraylist[$offset])){
return TRUE;
} else {
return FALSE;
}
}
function offsetGet($offset){
return $this->arraylist[$offset];
}
function offsetSet($offset, $value){
if($offset){
$this->arraylist[$offset] = $value;
} else {
$this->arraylist[] = $value;
}
}
function offsetUnset($offset){
unset($this->arraylist[$offset]);
}
function current() {
return $this->arraylist[$this->currentIndex];
}
function key() {
return $this->currentIndex;
}
function next() {
return $this->arraylist[$this->currentIndex++];
}
function rewind() {
$this->currentIndex = 0;
}
function valid() {
if(array_key_exists($this->currentIndex, $this->arraylist)) {
return true;
} else {
return false;
}
}
function append($value) {
$this->arraylist->offsetSet(null, $value);
}
function length() {
return count($this->arraylist);
}
function getIterator() {
return $this;
}
}
$nArray = new NArray();
$nArray[0] = 'a';
$nArray[1] = 'b';
$nArray[2] = 'c';
$nArray[3] = 'd';
foreach($nArray as $index => $item) {
echo $index . ' = '. $item . '<br />';
}
echo 'Counted Length Outside Class: '. count($nArray) ."<br>";
echo 'Counted Length Inside Class: '.$nArray->length();
echo "<br><br><br>";
show_source(__FILE__);
?>
Please ignore the fact that this should be an arrayobject because it is
simply a proof of concept, the use of an arrayaccess interface will be
used later to work with a sql dataset without actually loading all the
data in that dataset. A count value will be returned from num_rows type
commands without an internal array of the data ever existing.
Hope this helps.
Previous Comments:
------------------------------------------------------------------------
[2004-10-29 11:52:53] kevin at oceania dot net
check your code.
If this is a cut and paste you have typo here:
$length = $isnt->length;
should read
$length = $inst->length;
------------------------------------------------------------------------
[2004-09-16 14:44:52] kevin at stormtide dot ca
Description:
------------
IN SPL: The ArrayAccess interface does not correcly work with the root
level count() function. I realise that the ArrayObject interface
supposedly does, however that class requires an array as the basis, and
thus is not useful for virtual arrays (like abstracting a large db
without ever loading it)
Reproduce code:
---------------
class somearray implements ArrayAccess {
... overloads and such.
function length() {
return count($this->internalarrayorabstract);
}
}
$inst = new somearray();
$inst[0] = 'foo';
$inst[1] = 'foo';
$inst[2] = 'foo';
$length = $isnt->length;
$countedlength = count($inst);
//$length and $countedlength will differ in value with the latter
returning 1 always and the former the correct val.
Expected result:
----------------
$countedlength == $length
Actual result:
--------------
$countedlength == 1
------------------------------------------------------------------------
--
Edit this bug report at http://bugs.php.net/?id=30113&edit=1