Nested scope

Intent

Create a composable runtime hierarchy of data and behaviour

Motivation

We want dynamic means of modifying complex runtime structures

Implementation

Use php magic to dynamically dispatch requests to parent methods

Examples

class scope {
  var $parent;
  function __call( $name ) {
    if(isset($parent[$name]) { return $parent[$name](); }
    throw( new someException() );
  }

  function let( $name, $value ) {
    if(is_object($value)) { 
      //hygiene
      if(isset($this->$name)) { $this->$name->parent = null; }
      $this->$name = $value;
      $this->$name->parent = $this;
  }
}

//alternative let
function let($parent, $name, $class) {
  $parent->$name = new $class();
  $parent->$name->parent = array($parent,$name);
}

?>

Notes

• A concept related to and very often mistaken (mixed) (by me) with (for) closures
• the let method can be folded into __set if we want this behaviour to the default for assignments to object fields