typename liability for inherited typedefs

[Levent]

Please consider the following Parent and Child template classes:

template <class T>
class Parent {
public:
typedef T type;
typedef T& ref;
/* pack of typedefs */
};

template<class T>
class Child: public Parent<T>
type data;
public:
ref get() {return data;}
};

(gcc) warning: `Child<T>::type' is implicitly a typename
implicit typename is deprecated
(same for ref)

which emphasizes the use and importance of `typename' keyword and is
great, unlike MS compiler.... And thus I guess, above code is not
acceptable according to the standards...

But, where does the typename supposed to appear for derived typedefs
(without listing them all over again in Child)?

 

[Kai-Uwe Bux]

Please consider the following Parent and Child template classes:

template <class T>
class Parent {
public:
typedef T type;
typedef T& ref;
/* pack of typedefs */
};

template<class T>
class Child: public Parent<T>

insert:

{
typedef typename Parent<T>::type type;

type data;
public:
ref get() {return data;}
};

[snip]


Best

Kai-Uwe Bux

 

[Larry I Smith]

Please consider the following Parent and Child template classes:

template <class T>
class Parent {
public:
typedef T type;
typedef T& ref;
/* pack of typedefs */
};

template<class T>
class Child: public Parent<T>
type data;
public:
ref get() {return data;}
};

(gcc) warning: `Child<T>::type' is implicitly a typename
implicit typename is deprecated
(same for ref)

which emphasizes the use and importance of `typename' keyword and is
great, unlike MS compiler.... And thus I guess, above code is not
acceptable according to the standards...

But, where does the typename supposed to appear for derived typedefs
(without listing them all over again in Child)?

template <class T>
class Parent {
public:
typedef T type;
typedef T& ref;
/* pack of typedefs */
};

template<class T>
class Child: public Parent<T> {
typename Parent<T>::type data;
public:
typename Parent<T>::ref get() {return data;}
};

Regards,
Larry