newbie class templates question

Hi there,

This is my 1st post on this board, so plz don´t hesitate
to welcome me by replying massively to the question
below concerning a class template implementation.
I included only part of the code:

template <class T>
class pr {
T value1, value2;
public:
pr (T first, T second)
{value1=first; value2=second;}
T module () {return 0;}
};

template <>
class pr<int>{
int value1, value2;
public:
pr (int first, int second)
{value1=first; value2=second;}
int module ();
};

template <>
int pr<int>::module() {
return value1%value2;
}



the BOLD part of the code returns the following error
while compiling in borlands C5.5 compiler:

invalid explicit specialization of 'pr<int>::module()' etc.

Did I overlook something :confused:

Thanx,

Martijn

well i dunno

template <>
class pr<int>{
int value1, value2;
public:
pr (int first, int second)
{value1=first; value2=second;}
int module ();
};

template <>
int pr<int>::module() {
return value1%value2;
}

invalid explicit specialization of 'pr<int>::module()' etc

you don't need a template here if it is always going to be an int returned. I don't think you want the modulus of two chars, etc. You may want to make a template if your going to use numeric types other than ints such as long, if that is the case just use the regular template syntax. And since % only works on integral type int, long, char, unsigned char... a template won't work very well. Such as a double won't work with the % operator.

Code:

---

class pr
{
    int value1, value2;
public:
    pr (int first = 1, int second = 1)
        {value1=first; value2=second;}
    int module ();
};

int pr::module() {
return value1%value2;
}

---

if you want a template your original ( with initialization in constructor which causes problems with some data type obviously) :

Code:

---

template <class T>
class pr {
T value1, value2;
public:
pr (T first = 1, T second = 1)
{value1=first; value2=second;}
T module () {value1 % value2;}
};

    pr <int> nPr;
    pr<char> cPr; //will work not much value
    pr<string> sPr; //will not work the constructor cannot use the string template becuase of the constructor uses int
    pr<double> d1( 10, 4 );//will work
    d1.module( );//fails on compile % is not an operator for double

---

Basically this is not a good use of a template, its not needed here.

You'll also have to do more checking in your module method to avoid dividing by zero. Bad Ju Ju...

dang