How to save a PHP closure(lambda function) into $this->var and call it later from another method of the same class?

Question

I have a class

class SomeClass {
  private $someVar;

  public function Init($func) {
    $this->someVar = $func;
  }

  public function DoSomething() {
    $this->someVar("asdasdasd");
  }
}

$obj = new SomeClass();
$obj->Init(function ($param){var_dump($param);});
$obj->DoSomething();

When I call the method DoSomething, I get an error that SomeClass::someVar() is undefined method. But when I use the debugger, I see that it is a closure object. If I save the function into a local variable ($someVar without $this) and call it in the Init() function, it works just fine. But I don't want to call the function there. I want to call it later.

Even if I save it into $this->someVar and call it in the same scope it does not work.

Answer 1

Maybe you should simply try this :

public function DoSomething()
{
  $tmpVar = $this->someVar;
  $tmpVar("asdasdasd");
}

or, if you prefer, this :

public function DoSomething()
{
  call_user_func($this->someVar, "asdasdasd");
}

Answer 2

Here you have other options: How to call a closure that is a class variable?

Basically:

• 1. Force the call to the __invoke magic method:

     $myInstance = new MyClass(); $myInstance->lambda->__invoke();

• Or 2. Capture the method call:

  class MyClass
  {
      private $lambda;
  
      public function __construct()
      {
          $this->lambda = function() {
              echo "Hello world!\n";
          };
      }
  
      public function __call($name, $args)
      {
          return call_user_func_array($this->$name, $args);
      }
  }
  

Answer 3

Try

public function DoSomething()
{
    call_user_func( $this->someVar, 'test');
}