Archon mixin system pseudocode

pseudocode.php

<?php

// This class has functionality which can be used by many other classes.
class CommonFunctionalityClass {
  function doSomethingCommon() {
    $this->supportingFunction();
  }
  function supportingFunction() {
    echo(“hi”);
  }
}

// This class wants the `doSomethingCommon` method, but it can’t extend
// CommonFunctionalityClass because it already extends SomeIrrelevantClass.
class ClassThatWantsCommonFunctionality extends SomeIrrelevantClass {
  // PHP’s magic __call method, evoked when $method doesn’t exist.
  function __call($method, $args) {
    if ($method == “doSomethingCommon”) {
      eval(“CommonFunctionalityClass::doSomethingCommon(“ . $args . “)”);
    }
    else {
     // raise an error
    }
  }
}

// Now you can call the common functionality ...
$object = new ClassThatWantsCommonFunctionality();

// ... and this nonexistent instance method is intercepted by PHP
// and handled with `__call`:
$object->doSomethingCommon();

// Ultimately, this leads to the following code being eval’d:
CommonFunctionalityClass::doSomethingCommon();

// NOTE: This is a simplification!

?>