php oop: making anonymous functions in an array inside a class

Question

I want to store anonymous functions in an array inside a class. Below is my working codes. But I don't understand why I must pass in values in the second argument while I have already declare it to be an empty array by default if nothing is set from outside.

-- public function methods($method = "init",$options = array()){--

Any ideas?

class myclass {

    public function __construct() {}

    public function methods($method = "init",$options = array()){

        $methods = array(
            "init" => function($options){
                return $options;
            },

            "run" => function($options){
                return $options;
            },
        );

        return call_user_func_array( $methods[$method], $options);
    }
}

$obj = new myclass();
var_dump($obj->methods("init",array("hello world!"))); // string 'hello world!' (length=12) --> correct.
var_dump($obj->methods("init",array())); // Warning: Missing argument 1 for myclass::{closure}() in...refer to -> "init" => function($options){
var_dump($obj->methods("init")); // Warning: Missing argument 1 for myclass::{closure}() in...refer to -> "init" => function($options){

I thought it should return these as results,

var_dump($obj->methods("init",array())); // array (size=0)  empty
var_dump($obj->methods("init")); //  array (size=0)  empty

Hieu Le · Accepted Answer · 2013-08-03 14:37:54Z

4

The correct closure declaration for your case is:

$methods = array(
    "init" => function() use ($options){
        return $options;
    },

    "run" => function() use ($options){
        return $options;
    },
);

If you including the $options variables in your closure declaration, its scope will be the closure itself. Therefore, there will be a new $options variable created and overriding the $options variables in the outer function.

By using the use keyword, you tell PHP that you want to use the passed $options variable (which is currently initiated).

Now, you can omit the second parameter in the call_user_func_array call as follows

call_user_func_array($methods[$method])

edited Aug 3, 2013 at 14:37

answered Aug 3, 2013 at 14:30

Hieu Le

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1 Comment

Orangepill Over a year ago

then change to call_user_func

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