Why can't I overload constructors in PHP?

php oop overloading constructor
tom picture tom · Jan 30, 2010 · Viewed 65.4k times · Source

I have abandoned all hope of ever being able to overload my constructors in PHP, so what I'd really like to know is why.

Is there even a reason for it? Does it create inherently bad code? Is it widely accepted language design to not allow it, or are other languages nicer than PHP?

Answer

Alex Weinstein picture Alex Weinstein · Feb 1, 2010

You can't overload ANY method in PHP. If you want to be able to instantiate a PHP object while passing several different combinations of parameters, use the factory pattern with a private constructor.

For example:

public MyClass {
    private function __construct() {
    ...
    }

    public static function makeNewWithParameterA($paramA) {
        $obj = new MyClass(); 
        // other initialization
        return $obj;
    }

    public static function makeNewWithParametersBandC($paramB, $paramC) {
        $obj = new MyClass(); 
        // other initialization
        return $obj;
    }
}

$myObject = MyClass::makeNewWithParameterA("foo");
$anotherObject = MyClass::makeNewWithParametersBandC("bar", 3);

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