Iterator__

Purpose

To make an object iterable and to make it appear like a collection of objects.

Examples

• to process a file line by line by just running over all lines (which have an object representation) for a file (which of course is an object, too)

Note

Standard PHP Library (SPL) defines an interface Iterator which is best suited for this! Often you would want to implement the Countable interface too, to allow count($object) on your iterable object

UML Diagram

.. image:: uml/uml.png :alt: Alt Iterator UML Diagram :align: center

Code

You can also find this code on GitHub_

Book.php

.. literalinclude:: Book.php :language: php :linenos:

BookList.php

.. literalinclude:: BookList.php :language: php :linenos:

Test

Tests/IteratorTest.php

.. literalinclude:: Tests/IteratorTest.php :language: php :linenos:

.. _GitHub: https://github.com/DesignPatternsPHP/DesignPatternsPHP/tree/main/Behavioral/Iterator .. __: http://en.wikipedia.org/wiki/Iterator_pattern