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So you can't make an abstract static function in php.

The alternatives as I see them are to:

  1. Make the function non-static and write extra boilerplate code to create and store the object so I can access that function.

    abstract class Foo {

  abstract public function bar();

}

abstract class Good {

  public function bar() {
    ...
  }

}

// boilerplate to access Good->bar()... potentially a lot in multiple files
$g = new Good();
$g->bar();

  2. Fill in the static function in my abstract class with a BadMethodCallException, so that any call to a child class which doesn't implement it will throw the exception.

    abstract class Foo {

  public static function bar() {
    throw new BadMethodCallException("Not Implemented By Child Class :(");
  }

}

class Good extends Foo {

  public static function bar() {
    // ...
  }

}

class Bad extends Foo {

  // no bar implementation

}

Good::bar(); // works
Bad::bar():  // exception

I'm leaning towards 2. but was wondering if there's any community consensus on this issue or best practices.

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jtfairbank
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  • How would you imagine calling your static abstract method? Perhaps if you explain how you'd like to call the function we can propose a solution. – scragar May 22 '14 at 10:29
  • I'd like to implement the static abstract method in a child class, then call that. For example: `Good::bar()`. – jtfairbank May 22 '14 at 11:06
  • If you're going to know the class you're using that makes an abstract stub useless for it, since it's not required for the abstract, only for the actual class. – scragar May 22 '14 at 11:09
  • Yes and no. I find it useful as a reminder to implement that function across all child classes- it's my way of noting that you should have this function available. In the program itself it may not be used, but it is still helpful while writing the code. – jtfairbank May 22 '14 at 11:11

1 Answers1

1

I ended up making an interface with a static function, then implementing the interface in the abstract class. This forces the child classes to define the method, which is basically what I wanted with an abstract static function.

interface ModelFactoryInterface {
  public static function offer();
}

abstract class ModelHelper implements ModelFactoryInterface {

  protected $tester;

  public function __construct($tester) {
    $this->tester = $tester;
  }

}

/* Location
 * ------------------------------------------------------ */
final class LocationHelper extends ModelHelper {

  public static function offer() {
    return new Location(...)
  }

}
jtfairbank
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