no member function declaired in class

[celoz0828]

I'm getting the following error:


select.cpp:4: error: no member function 'select' declared in 'Sortings<int, intintCompare>'
select.cpp:7: error: no 'void Sortings<Elem, Comp>::select(Elem*, unsigned int)' member function declared in class 'Sortings<Elem, Comp>'

and I have no clue whats going on. I have other files the same exact way and they work, any help?

header file

#ifndef _SORTING_H_
#define _SORTING_H_

#include <iostream>
#include <cstring>
using namespace std;

template <class Elem, class Comp>
class Sortings
{
 public:
  static void merge(Elem *arr, unsigned int n);
  //  static void quick(Elem *arr, unsigned int n); do merge or this one
  static void select(Elem *arr, unsigned int n);
  static void shell(Elem *arr, unsigned int n);
  static void radix(Elem *arr, unsigned int n); // when using radix, Comp should be a class
  // with a static method "uintVal(...)" that gives an unsigned int representation of the item
 private:
  // These are all optional, add or remove as functions as you need
  static const unsigned int THRESHOLD = 3; // used by shell
  static const unsigned int RADIX = 16; // used by radix
  static void insert2(Elem *arr, unsigned int incr, unsigned int n);
  static void swap(Elem *arr, unsigned int, unsigned int);
  static void mergeRecurse(Elem *arr, Elem tmp[], unsigned int l, unsigned int r);
};

class intuival
{
public:
  static unsigned int uintVal(int n);
};

class intintCompare
{
 public:
  static bool lt(int, int);
  static bool gt(int, int);
  static bool eq(int, int);
};

class strstrCompare
{
 public:
  static bool lt(char*, char*);
  static bool gt(char*, char*);
  static bool eq(char*, char*);  
};

#endif 

#include "sorting.hh"

template class Sortings<int,intintCompare>;
template void Sortings<int,intintCompare>::select(int*, unsigned int);

template<class Elem, class Comp>
void Sortings<Elem,Comp>::select(Elem* arr, unsigned int n)
{
int i,j,min;
for(i=0;i<n;i++)
min = i;
for (j = 1; j<n && Comp::lt(arr[j], arr[min];j++)
min = j
swap(arr,min,i);
}

[firedraco]

Uh, all your member functions are static. You should probably go look up what that means.

[celoz0828]

I can't touch the header file. that was given to me like that by my professor.

[kbw]

It's not clear what are you doing?

Are you providing the implementation for the methods declared in the header file?

It would help if you indented your code.

[celoz0828]

I am implementing the methods in the header file. I have them all started off the same way

#include "sorting.hh"

template class Sortings<int,intintCompare>;
template void Sortings<int,intintCompare>::select(int*, unsigned int);

template<class Elem, class Comp>

obviously formatting it to each method. This method is the one I'm getting a problem for though. So I don't understand what's wrong.

[kbw]

The syntax isn't quite right.

You have to complete the implementation like this:

template <class Elem, class Comp>
void Sorting<Elem, Comp>::merge(Elem *arr, unsigned int n)
{
    // place your implementation here
}

template <class Elem, class Comp>
void Sorting<Elem, Comp>::select(Elem *arr, unsigned int n)
{
    // place your implementation here
}

// and so on ... 

If you want to preinstantiate the class for Sortings<int, intintCompare>, you add this at the end of the .cpp file.

template class Sortings::<int, intintCompare>;

There's an example here:
http://www.cplusplus.com/forum/unices/7252/#msg33687

[celoz0828]

its still not finding the function. it keeps saying that select is not a member function declared in Sortings<Elem,Comp> even though its right there in the header file. I don't understand.

[SIK]

can you please list a skeleton view of your header file - ie minus the inner implementations (if they do currently exist) of the Sorting class methods?

[celoz0828]

So I just moved all files into another directory, and that caused it to work as is. Weird.