Linker Error Help

This happens when an object (in your case, a function) is defined in two different cpp files.

Also note that if an object is defined in a file, it will also be defined in all files that include that file. No, include guards (the #ifndef #define #endif tags) don't protect you against this.

Be careful to
- never define things in header files
- never include cpp files in anything
and this kind of problem should not happen.

EDIT: and by "defined" I mean writing things like :
int Variable; //Variable is defined
void Function( void ) { return; } //Function is defined

What you CAN do, however, is things like :
extern int Variable; // Variable is declared
void Function( void ); //Function is declared

What you usually do is define a thing in only ONE place, then declare it everywhere where you need it.

Victor Nicollet, INT13 game programmer

[edited by - ToohrVyk on March 30, 2004 1:50:09 PM]

quote:

---

Original post by ToohrVyk
- never declare things in header files

---

Declarations are fine. Definitions aren't.

Declarations:

extern int foo;
int bar();
class baz;

Definitions:

int foo;
int bar() {}
class baz {};


[edited by - Fruny on March 30, 2004 1:48:27 PM]

all is well now, thank you!

Scotty.

Argh, Fruny, if only you knew...
Every time I wanted to type "define" I typed "declare", and had to write it again. I guess I missed one... But I edited it before you answered

(BTW: concours (Mines, puis Centrale, puis X, puis ENS) dans 27 jours... stress)

Victor Nicollet, INT13 game programmer

[edited by - ToohrVyk on March 30, 2004 1:57:23 PM]

quote:

---

Original post by ToohrVyk
(BTW: concours dans 27 jours... stress)

---

Quelle école?