oop - PHP SplObjectStorage Cannot create within a class -

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• getting error trying initialize public class variable using dirname() outside method 9 answers

would possible initialize protected splobjectstorage map within class? seem running error whenever try this. similar example below:

class {    protected $a = new splobjectstorage();    ...  } 

you need use constructor

class {   public function __construct() {      $this->a = new splobjectstorage();   }    protected $a;    ... }