(PECL pthreads >= 3.0.0)
The Volatile class is new to pthreads v3. Its introduction is a consequence of the new immutability semantics of Threaded members of Threaded classes. The Volatile class enables for mutability of its Threaded members, and is also used to store PHP arrays in Threaded contexts.
Example #1 New immutability semantics of Threaded
<?php
class Task extends Threaded
{
public function __construct()
{
$this->data = new Threaded();
// attempt to overwrite a Threaded property of a Threaded class (invalid)
$this->data = new StdClass();
}
}
var_dump((new Task())->data);
以上例程的输出类似于：
RuntimeException: Threaded members previously set to Threaded objects are immutable, cannot overwrite data in %s:%d
Example #2 Volatile use-case
<?php
class Task extends Volatile
{
public function __construct()
{
$this->data = new Threaded();
// attempt to overwrite a Threaded property of a Volatile class (valid)
$this->data = new StdClass();
}
}
var_dump((new Task())->data);
以上例程的输出类似于：
object(stdClass)#3 (0) {
}