为变量分配静态函数

Question

Is there any way to assign a static function to a variable, or accomplishing this in some other way?

class my_class{
     public static function my_method($a){
        return $a;
     }
}

$some_func = my_class::my_method;

$someAnonFunc = function($a) use ($some_func){
    return $some_func($a);
}

$inst = new SomeOtherClass(); //Defined somewhere else, in some other file

$inst->someMethod($a, $someAnonFunc);

At this point, I get:

Fatal error: Undefined class constant 'my_method'

Answer 1

Functions are not first class in PHP .. strings are. You would have to use call_user_func if you wanted to stick with the :: syntax as one unit:

$some_func = 'my_class::my_method';
$someAnonFunc = function ($a) use ($some_func) {
   return call_user_func($some_func, $a);
}

Trying to run $some_func() will not work since it will treat the colons as part of the function name.