C++ (Qt)
template<typename K, typename V> class AbstractBaseDialog : public QDialog
{
public:
    typedef QHash<K, V> Result;
    explicit AbstractBaseDialog(QWidget *parent = 0);
    virtual ~AbstractBaseDialog() {}
    ...
};
 
class AbstractFormattingDialog : public AbstractBaseDialog<QString,QStringList>
{
    Q_OBJECT
public:
    typedef Result::ConstIterator Iterator;
    explicit AbstractFormattingDialog(QStringList &source, QWidget *parent = 0);
    virtual ~AbstractFormattingDialog() {}
    ...
protected:
    ...
    virtual void _loadData() = 0;
    ...
};

error: 'AbstractBaseDialog' is not a template type
 template<class K, class V> class AbstractBaseDialog : public QDialog
                                  ^
error: expected template-name before '<' token
 class AbstractFormattingDialog : public AbstractBaseDialog<QString,QStringList>
                                                           ^
error: expected '{' before '<' token
error: expected unqualified-id before '<' token

C++ (Qt)
friend class AbstractBaseDialog;

C++ (Qt)
template<typename K, typename V>
friend class AbstractBaseDialog;