To treat a group of objects the same way as a single instance of the object.

To treat a group of objects the same way as a single instance of the object.

* a form class instance handles all its form elements like a single instance of the form, when`render()` is called, it

subsequently runs through all its child elements and calls`render()` on them

*`Zend_Config`: a tree of configuration options, each one is a`Zend_Config` object itself


@startuml

class Form {

protected elements

+render($indent = 0)

+addElement(FormElement $element)

}

abstract class FormElement {

+render($indent = 0)

}

class InputElement {

+render($indent = 0)

}

class TextElement {

+render($indent = 0)

}

FormElement <|.. TextElement

FormElement <|.. InputElement

FormElement <|.. Form

@enduml