Question

I’ll like to know if this is a bug or wrong implementation ….. am try to check if class_exist

My Class

namespace servers\testing ;

class HelloWord
{
    function hello()
    {
        echo "hello World" ;
    }
}

Testing

use servers\testing\HelloWord as OkWorld ;

$okWolrd = new OkWorld() ;
$helloWorld  = new \servers\testing\HelloWord() ;

var_dump($okWolrd);  //object(servers\testing\HelloWord)[1]
var_dump(class_exists('servers\testing\HelloWord')); //true 
var_dump(class_exists('OkWorld')); //false


$declearedClasses = get_declared_classes() ;

var_dump(in_array('servers\testing\HelloWord', $declearedClasses)); //true
var_dump(in_array('OkWorld', $declearedClasses)); //false


var_dump($okWolrd instanceof $helloWorld); //true but OkWolrd needed to be initiated before it works

Question

Does it mean that OkWord is not a valid PHP class ?? note that new OkWorld() works fine.

How do you verify that OkWord exists without deceleration ?

Edit 1

I know that OkWorld is an alias but its a reference to servers\testing\HelloWord which is a valid class …

Thanks

Answer 1

I think it’s neither a bug nor a wrong implementation.

OKWorld is not a class, it’s an alias, the interpreter will replace it with HelloWord whenever it exists. But the interpreter will not search the strings, so the function class_exists will get the string OKWorld and search for the corresponding class, which doesn’t actually exist! What actually exists is an alias.