templated return

[RA Scheltema]

hi all,


I have the following situation:

template <typename _Ta>
class A
{
template <size_t _Tsize>
struct B
{
char buffer[_Tsize];
};
};


The thing is, I need to define a function which returns struct B, but not
with a pre-defined template-argument _Tsize. I have been trying some things
like:

template <typename _Ta>
class A
{
...
template <typename _Tsize>
B<_Tsize> GetB()
{
return B<_Tsize>();
}
};


and attempted to call this function as follows:

A<int> a;
A<int>::B<1> b = a.GetB<1>();


But this doesn't seem to make it through my Visual C++ 6.0 compiler (wierd
stuff with operators for the std::vector are popping up). Can anybody tell
me if there even is a standard c++ way for doing this ?



thanks ahead,
richard

 

[red floyd]

hi all,


I have the following situation:

template <typename _Ta>
class A
{
template <size_t _Tsize>
struct B
{
char buffer[_Tsize];
};
};


The thing is, I need to define a function which returns struct B, but not
with a pre-defined template-argument _Tsize. I have been trying some things
like:

template <typename _Ta>
class A
{
...
template <typename _Tsize>
B<_Tsize> GetB()
{
return B<_Tsize>();
}
};


and attempted to call this function as follows:

A<int> a;
A<int>::B<1> b = a.GetB<1>();


But this doesn't seem to make it through my Visual C++ 6.0 compiler (wierd
stuff with operators for the std::vector are popping up). Can anybody tell
me if there even is a standard c++ way for doing this ?



thanks ahead,
richard

Rename your template parameters. Leading underscore followed by a cap is reserved.

 

[Victor Bazarov]

I have the following situation:

template <typename _Ta>

If this is your code, you shouldn't be using such names. Any name
that starts with an underscore and a capital letter is _reserved_.
Why in the world do you need the leading underscore?

class A
{
template <size_t _Tsize>

Same here.

struct B
{
char buffer[_Tsize];
};
};


The thing is, I need to define a function which returns struct B, but not
with a pre-defined template-argument _Tsize. I have been trying some things
like:

template <typename _Ta>
class A
{
...
template <typename _Tsize>
B<_Tsize> GetB()
{
return B<_Tsize>();
}
};


and attempted to call this function as follows:

A<int> a;
A<int>::B<1> b = a.GetB<1>();


But this doesn't seem to make it through my Visual C++ 6.0 compiler (wierd
stuff with operators for the std::vector are popping up). Can anybody tell
me if there even is a standard c++ way for doing this ?

Try a different compiler. VC++ 6 is really bad wrt templates.

Victor

 

[Andrey Tarasevich]

...
I have the following situation:

template <typename _Ta>
class A
{
template <size_t _Tsize>
struct B
{
char buffer[_Tsize];
};
};


The thing is, I need to define a function which returns struct B, but not
with a pre-defined template-argument _Tsize. I have been trying some things
like:

template <typename _Ta>
class A
{
...
template <typename _Tsize>
B<_Tsize> GetB()
{
return B<_Tsize>();
}
};
...

This doesn't make much sense. Template 'B' is declared as accepting a
non-type parameter (a value of type 'size_t') and you are trying to
specialize it with type argument.

Here again, you are trying to specialize 'GetB' with non-type argument,
while template 'GetB' expects a type argument.