call_user_func within class context (with $this defined)

Question

Is there a way how to execute closure in PHP5.3 within a context of an object?

class Test {
    public $name='John';

    function greet(){
        eval('echo "Hello, ".$this->name;');

        call_user_func(function(){
            echo "Goodbye, ".$this->name;
        });
    }
}
$c = new Test;
$c->greet();

The eval() would work fine, however call_user_func will have no access to $this. (Using $this when not in object context). I am passing "$this" as an argument to closure right now, but that's not exactly what I need.

Unfortunately call_user_func(array($this,function(){ .. })); wouldn't work, which would be ideal syntax for this. — romaninsh
– romaninsh, Commented Apr 5, 2011 at 9:26

Gordon · Accepted Answer · 2011-04-05 09:30:57Z

6

Access to $this is not possible from lambda or closure as of PHP 5.3.6. You'd either have to assign $this to a temp var and use that with use (which means you will only have the public API available) or pass in/use the desired property. All shown elsewhere on this site, so I won't reiterate.

Access to $this is available in Trunk though for PHP.next: http://codepad.viper-7.com/PpBXa2

answered Apr 5, 2011 at 9:30

Gordon

318k76 gold badges548 silver badges566 bronze badges

Sign up to request clarification or add additional context in comments.

2 Comments

romaninsh Over a year ago

How did you manage to answer questions so quickly btw? Is there a live question feed?

Gordon Over a year ago

@roman I answered this one pretty late, didn't I? Don't know if there is a live feed. I just press F5 frequently :)

deceze · Accepted Answer · 2011-04-05 09:27:46Z

4

For an actual closure, this is about the only way to do it:

$obj = $this;
call_user_func(function () use ($obj) {
    echo "Goodbye, " . $obj->name;
});

It's probably more elegant to pass the object as parameter as suggested in the other answers (and probably as you're already doing).

answered Apr 5, 2011 at 9:27

deceze♦

525k89 gold badges806 silver badges954 bronze badges

1 Comment

igorw Over a year ago

Was about to suggest this. Usually you do $that = $this;. At least in JavaScript.

user235064 · Accepted Answer · 2011-04-05 09:25:10Z

0

what about:

class Test {
    public $name='John';

    function greet(){
        eval('echo "Hello, ".$this->name;');

        call_user_func(function($obj){
            echo "Goodbye, ".$obj->name;
        }, $this);
    }
}
$c = new Test;
$c->greet();

answered Apr 5, 2011 at 9:25

user235064

1 Comment

romaninsh Over a year ago

That's what i'm using now, but it's not exactly setting the context.

Headshota · Accepted Answer · 2011-04-05 09:25:45Z

0

call_user_func(function($name){
            echo "Goodbye, ".$name;
        }, $this->Name);

answered Apr 5, 2011 at 9:25

Headshota

21.4k13 gold badges63 silver badges82 bronze badges

Collectives™ on Stack Overflow

call_user_func within class context (with $this defined)

4 Answers 4

2 Comments

1 Comment

1 Comment

Comments

Your Answer

Linked

Hot Network Questions

Collectives™ on Stack Overflow

4 Answers 4

2 Comments

1 Comment

1 Comment

Comments

Your Answer

Sign up or log in

Post as a guest

Linked

Related