<?php
class MyClass {
    private $ErrorHandler = null;
 
 
    // Зарегистрировать обработчик ошибок
    public function RegisterErrorHandler($ErrorHandlerFn) {
        $this->ErrorHandler = $ErrorHandlerFn;
    }
 
 
    // Симуляция ошибки
    public function TestError(){
        if(is_callable($this->ErrorHandler)) { // Если определен обработчик ошибок
            call_user_func($this->ErrorHandler,'Текст ошибки');
        }
    }
 
}
 
 
$myClass = new MyClass();
 
$myClass->RegisterErrorHandler(function($errorText){
    echo $errorText;
});
 
$myClass->TestError();

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