template id does not match any template declaration?

[Alex Buell]

This is what I'm trying to compile with GCC 3.4.4 under Linux. The
error I'm getting is:

g++ -s -O3 -Wall class2.cc -o class2
class2.cc:25: error: template-id `uppercase<>' for `char
container<char>::uppercase()' does not match any template declaration
class2.cc:25: error: invalid function declaration make: *** [class2]
Error 1

What's wrong with it? The code is as below. Thanks for any hints
offered.

#include <iostream>

using namespace std;

template<class T>
class container
{
T element;
public:
container (T arg) { element = arg; }
T increase () { return ++element; }
};

template<>
class container<char>
{
char element;
public:
container (char arg) { element = arg; }
char uppercase();
};

template<>
char container<char>::uppercase()
{
if ((element >= 'a') && (element <= 'z'))
element += 'A' - 'a';

return element;
}

int main()
{
container<int> myint(7);
container<char> mychar('j');

cout << myint.increase() << endl;
cout << mychar.uppercase() << endl;

return 0;
}

 

[Victor Bazarov]

This is what I'm trying to compile with GCC 3.4.4 under Linux. The
error I'm getting is:

g++ -s -O3 -Wall class2.cc -o class2
class2.cc:25: error: template-id `uppercase<>' for `char
container<char>::uppercase()' does not match any template declaration
class2.cc:25: error: invalid function declaration make: *** [class2]
Error 1

What's wrong with it? The code is as below. Thanks for any hints
offered.

#include <iostream>

using namespace std;

template<class T>
class container
{
T element;
public:
container (T arg) { element = arg; }
T increase () { return ++element; }
};

template<>
class container<char>
{
char element;
public:
container (char arg) { element = arg; }
char uppercase();
};

template<>

Drop the line above. What you're doing here is _definining_, not

char container<char>::uppercase()
{
if ((element >= 'a') && (element <= 'z'))
element += 'A' - 'a';

return element;
}

int main()
{
container<int> myint(7);
container<char> mychar('j');

cout << myint.increase() << endl;
cout << mychar.uppercase() << endl;

return 0;
}

V

 

[Alex Buell]

Drop the line above. What you're doing here is _definining_, not
_specialising_. You've already specialised it. Now, 'template<>' is
extraneous.

Thank you, that did the trick. I haven't coded C++ for a very long time
and I'm trying to get back into it, with all those new and wonderful
features that's been added since the early 1990s.

Cheers,
Alex