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68 lines
1.2 KiB
ReStructuredText
68 lines
1.2 KiB
ReStructuredText
`Visitor`__
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===========
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Purpose
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-------
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The Visitor Pattern lets you outsource operations on objects to other
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objects. The main reason to do this is to keep a separation of concerns.
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But classes have to define a contract to allow visitors (the
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``Role::accept`` method in the example).
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The contract is an abstract class but you can have also a clean
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interface. In that case, each Visitor has to choose itself which method
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to invoke on the visitor.
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UML Diagram
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-----------
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.. image:: uml/uml.png
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:alt: Alt Visitor UML Diagram
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:align: center
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Code
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----
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You can also find this code on `GitHub`_
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RoleVisitorInterface.php
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.. literalinclude:: RoleVisitorInterface.php
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:language: php
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:linenos:
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RoleVisitor.php
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.. literalinclude:: RoleVisitor.php
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:language: php
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:linenos:
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Role.php
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.. literalinclude:: Role.php
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:language: php
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:linenos:
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User.php
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.. literalinclude:: User.php
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:language: php
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:linenos:
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Group.php
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.. literalinclude:: Group.php
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:language: php
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:linenos:
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Test
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----
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Tests/VisitorTest.php
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.. literalinclude:: Tests/VisitorTest.php
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:language: php
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:linenos:
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.. _`GitHub`: https://github.com/domnikl/DesignPatternsPHP/tree/master/Behavioral/Visitor
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.. __: http://en.wikipedia.org/wiki/Visitor_pattern |