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<?php class A { public $avar; public function __isset($varname) { var_dump('__isset called'); return true; } } class B extends A { public function hasAVar(){ return property_exists($this, 'avar'); } public function hasBVar(){ return property_exists($this, 'bvar'); } public function issetVars($property) {return isset($this->{$property}); } } $b = new B(); var_dump($b->hasAVar()); var_dump($b->hasBVar()); var_dump($b->issetVars('avar')); var_dump($b->issetVars('bvar'));

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