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  </div>

  <div id="language.oop5.basic.new" class="sect2">
   <h3 class="title">new</h3>
   <p class="para">
    To create an instance of a class, a new object must be created and
    assigned to a variable.  An object will always be assigned when
    creating a new object unless the object has a
    <a href="language.oop5.decon.html" class="link">constructor</a> defined that throws an
    <a href="language.exceptions.html" class="link">exception</a> on error. Classes
    should be defined before instantiation (and in some cases this is a
    requirement).
   </p>
   <div class="example">
    <p><b>Example #5 Creating an instance</b></p>
    <div class="example-contents">
<div class="phpcode"><code><span style="color: #000000">
<span style="color: #0000BB">&lt;?php<br />$instance&nbsp;</span><span style="color: #007700">=&nbsp;new&nbsp;</span><span style="color: #0000BB">SimpleClass</span><span style="color: #007700">();<br /></span><span style="color: #0000BB">?&gt;</span>
</span>
</code></div>
    </div>

   </div>
   <p class="para">
    In the class context, it is possible to create a new object by
    <i>new self</i> and <i>new parent</i>.
   </p>
   <p class="para">
    When assigning an already created instance of a class to a new variable, the new variable
    will access the same instance as the object that was assigned. This
    behaviour is the same when passing instances to a function. A copy
    of an already created object can be made by
    <a href="language.oop5.cloning.html" class="link">cloning</a> it.
   </p>
   <div class="example">
    <p><b>Example #6 Object Assignment</b></p>
    <div class="example-contents">
<div class="phpcode"><code><span style="color: #000000">
<span style="color: #0000BB">&lt;?php<br />$assigned&nbsp;&nbsp;&nbsp;</span><span style="color: #007700">=&nbsp;&nbsp;</span><span style="color: #0000BB">$instance</span><span style="color: #007700">;<br /></span><span style="color: #0000BB">$reference&nbsp;&nbsp;</span><span style="color: #007700">=&amp;&nbsp;</span><span style="color: #0000BB">$instance</span><span style="color: #007700">;<br /><br /></span><span style="color: #0000BB">$instance</span><span style="color: #007700">-&gt;</span><span style="color: #0000BB">var&nbsp;</span><span style="color: #007700">=&nbsp;</span><span style="color: #DD0000">'$assigned&nbsp;will&nbsp;have&nbsp;this&nbsp;value'</span><span style="color: #007700">;<br /><br /></span><span style="color: #0000BB">$instance&nbsp;</span><span style="color: #007700">=&nbsp;</span><span style="color: #0000BB">null</span><span style="color: #007700">;&nbsp;</span><span style="color: #FF8000">//&nbsp;$instance&nbsp;and&nbsp;$reference&nbsp;become&nbsp;null<br /><br /></span><span style="color: #0000BB">var_dump</span><span style="color: #007700">(</span><span style="color: #0000BB">$instance</span><span style="color: #007700">);<br /></span><span style="color: #0000BB">var_dump</span><span style="color: #007700">(</span><span style="color: #0000BB">$reference</span><span style="color: #007700">);<br /></span><span style="color: #0000BB">var_dump</span><span style="color: #007700">(</span><span style="color: #0000BB">$assigned</span><span style="color: #007700">);<br /></span><span style="color: #0000BB">?&gt;</span>
</span>
</code></div>
    </div>

    <div class="example-contents"><p>The above example will output:</p></div>
    <div class="example-contents"><pre>
<div class="cdata"><pre>
NULL
NULL
object(SimpleClass)#1 (1) {
   [&quot;var&quot;]=&gt;
     string(30) &quot;$assigned will have this value&quot;
}
</pre></div>
    </pre></div>
   </div>
  </div>

  <div id="language.oop5.basic.extends" class="sect2">
   <h3 class="title">extends</h3>
   <p class="para">
    A class can inherit methods and members of another class by using the
    extends keyword in the declaration. It is not possible to extend multiple
    classes, a class can only inherit one base class.
   </p>
   <p class="para">
    The inherited methods and members can be overridden, unless the parent
    class has defined a method as <a href="language.oop5.final.html" class="link">final</a>,
    by redeclaring them with the same name defined in the parent class.
    It is possible to access the overridden methods or static members by
    referencing them with <a href="language.oop5.paamayim-nekudotayim.html" class="link">parent::</a>
   </p>
   <div class="example">
    <p><b>Example #7 Simple Class Inheritance</b></p>
    <div class="example-contents">
<div class="phpcode"><code><span style="color: #000000">
<span style="color: #0000BB">&lt;?php<br /></span><span style="color: #007700">class&nbsp;</span><span style="color: #0000BB">ExtendClass&nbsp;</span><span style="color: #007700">extends&nbsp;</span><span style="color: #0000BB">SimpleClass<br /></span><span style="color: #007700">{<br />&nbsp;&nbsp;&nbsp;&nbsp;</span><span style="color: #FF8000">//&nbsp;Redefine&nbsp;the&nbsp;parent&nbsp;method<br />&nbsp;&nbsp;&nbsp;&nbsp;</span><span style="color: #007700">function&nbsp;</span><span style="color: #0000BB">displayVar</span><span style="color: #007700">()<br />&nbsp;&nbsp;&nbsp;&nbsp;{<br />&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;echo&nbsp;</span><span style="color: #DD0000">"Extending&nbsp;class\n"</span><span style="color: #007700">;<br />&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</span><span style="color: #0000BB">parent</span><span style="color: #007700">::</span><span style="color: #0000BB">displayVar</span><span style="color: #007700">();<br />&nbsp;&nbsp;&nbsp;&nbsp;}<br />}<br /><br /></span><span style="color: #0000BB">$extended&nbsp;</span><span style="color: #007700">=&nbsp;new&nbsp;</span><span style="color: #0000BB">ExtendClass</span><span style="color: #007700">();<br /></span><span style="color: #0000BB">$extended</span><span style="color: #007700">-&gt;</span><span style="color: #0000BB">displayVar</span><span style="color: #007700">();<br /></span><span style="color: #0000BB">?&gt;</span>
</span>
</code></div>
    </div>

    <div class="example-contents"><p>The above example will output:</p></div>
    <div class="example-contents"><pre>
<div class="cdata"><pre>
Extending class
a default value
</pre></div>
    </pre></div>
   </div>
  </div>

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