public function removeAttributeValue($name){
        if(isset($this->attributes[$name])){
            $this->attributes[$name]->setNull();
        }
    }
public function removeAttributeValue($name){
        if(isset($this->attributes[$name])){
            $this->attributes[$name]->setNull();
        }
    }
public function removeAttributeValue ( $ name ) { if ( isset ( $ this -> attributes [ $ name ] ) ) { $ this -> attributes [ $ name ] -> setNull ( ) ; } }
Remove the actual value of an attribute, distinguish from empty value

@param string $name
Remove the actual value of an attribute distinguish from empty value