<?php
 
class A {
    function example() {
        echo "I am A::example() and provide basic functionality.<br />\n";
    }
}
 
class B extends A {
    function example() {
        echo "I am B::example() and provide additional functionality.<br />\n";
    }
 
    function main() {
        $this->example();
        parent::example();
    }
}
 
$b = new B;
 
// This will call B::example(), which will in turn call A::example().
$b->main();
 
// Saída:
// I am B::example() and provide additional functionality.
// I am A::example() and provide basic functionality.

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