2 <!DOCTYPE programlistingco PUBLIC "-//OASIS//DTD DocBook XML V4.1.2//EN" "http://www.oasis-open.org/docbook/xml/4.1.2/docbookx.dtd">
3 <programlistingco><areaspec><areaset id="ex.plco.const" coords=""><area id="ex.plco.c1" coords="4"/><area id="ex.plco.c2" coords="8"/></areaset><area id="ex.plco.ret" coords="12"/><area id="ex.plco.dest" coords="12"/></areaspec><programlisting>
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4 sub do_nothing_useful {
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9 $a->does_nothing_either();
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13 $c = "frog";
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17 </programlisting><calloutlist><callout arearefs="ex.plco.const"><para>
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18 These are calls to the constructor <function>new</function> in the object
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20 </para></callout><callout arearefs="ex.plco.ret"><para>
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21 This function returns a two-element list.
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22 </para></callout><callout arearefs="ex.plco.dest"><para>
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23 The <emphasis>destructor</emphasis> (<function>DESTROY</function>) for
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24 the object <literal>$b</literal> will be called automatically for this
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25 object since there can be no other references to it outside this function.
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26 </para></callout></calloutlist></programlistingco>