Thread: Templates and overloaded ==

Hey guys while working on a new crappy game I have stumbled across a problem. I am trying to use a template for a overloaded == in my class for collision. I am not good with words here is the code
character.h

Code:

#ifndef character_h
#define character_h

#include <allegro.h>

class character
{

public:
  character();
  character(int x, int y, const char *image1, const char *image2);
  template <class T>
  bool operator ==(T &obj);//handle collisions
  BITMAP *retImage() const;//returns current image  

/*************************************************************************
  Decided to make these variables public because they would be accessed 
  alot and functions to get and set them would be a waste
**************************************************************************/
  int xPos;//character's x coord for drawing
  int yPos;//character's y coord for drawing
  int currentImage;//to hold currrent image for switching image for movement
  int left;//left coord for collision
  int right;//right coord for collision
  int top;//top coord for collision
  int bottom;//bottom coord for collision

private:
  BITMAP *image[2];//The characters image  have two for "animation"

};

#endif

character.cpp

Code:

template <class T>
bool character::operator==(T &obj)
{
  
  return !(right < obj.left||obj.right < left||bottom < obj.top||obj.bottom < top);

}

All seems to be well with this but when I go to use it in my code for some detection I get an unresolved linker error. Its just a simple if statement eg.

Code:

if(player == enemy)
{
  //do stuff
}

Is there some way that I need to be handling the enemy. I know with templates and functions that you would do an <type> before you would call it but that doesn't seem reasonable here.

Dunno. What's the linker error (what symbol is unresolved)? It could be something else down the line that's causing the problem.

**EDIT**
Hm, isn't there something about templates always having to be defined inside the header (i.e. not in a separate .cpp file)? Not sure if that applies here, but it's worth a shot.

How new am I forgetting to post the error .

Code:

[Linker error] undefined reference to `bool character::operator==<character>(character&)'

[edit]Your method worked hunter. Thank you[/edit]