Thread: Problem accessing class method

This has been driving me insane, and I'm not sure what's wrong:

I have a header file (KeyValueComparator.h):

Code:

 #ifndef KEY_COMP
  2 #define KEY_COMP
  3 
  4 #include <string>
  5 #include <iostream>
  6 #include "KeyValuePair.h"
  7 
  8 using namespace std;
  9 
 10 class KeyValueComparator {
 11         public:
 12                 bool operator() (const KeyValuePair a, const KeyValuePair b) const;
 13 };
 14 
 15 #endif

and a .cpp file (KeyValueComparator.cpp):

Code:

 1 #include <iostream>
  2 #include <string>
  3 #include "KeyValueComparator.h"
  4 
  5 using namespace std;
  6 
  7 bool KeyValueComparator::operator() (const KeyValuePair a, const KeyValuePair b) const {
  8         if(a.count==b.count) {
  9                 if(a.str.compare(b.str)<=0)
 10                         return true;
 11                 else {
 12                         return false;
 13                 }
 14         }
 15         else {
 16                 if(a.count>b.count) {
 17                         return true;
 18                 }
 19                 else {
 20                         return false;
 21                 }
 22         }
 23 }

and finally a running file (Main.cpp):

Code:

  1 #include <algorithm>
  2 #include <map>
  3 #include <vector>
  4 #include <iostream>
  5 #include <fstream>
  6 #include <string>
  7 #include "KeyValuePair.h"
  8 #include "KeyValueComparator.h"
  9 using namespace std;
 10 
 11 int main () {
 12 
 13         KeyValuePair a;
 14         KeyValuePair b;
 15 
 16         KeyValueComparator cmp;
 17         bool check = cmp.operator(a,b);
 18 }

And I get the error:

Main.cpp: In function ‘int main()’:
Main.cpp:17: error: expected type-specifier before ‘(’ token


What's going on here?

Code:

bool check = cmp.operator(a,b);

You don't need "operator" it should be

Code:

cmp(a,b)

Jim

Having made the aforementioned change I get the following error:

Undefined symbols:
"KeyValueComparator:perator()(KeyValuePair, KeyValuePair) const", referenced from:
_main in ccciczWX.o
ld: symbol(s) not found
collect2: ld returned 1 exit status

This is a linker error saying it can't find your class implementation. Is you .cpp file being compiled/linked?

Jim