Declaring external functions within a class


I've created a Dynamic Link Library in C++ (Borland C++ Builder to be exact).
The DLL contains one class (in this case we'll call it class1) which has both public and private functions.

Is it possible to implement some of the "class1" functions outside of  the class1.cpp file?
i.e. implement functions func1 and func2 below in a separate .cpp file?

header file definition for class1:
~~~~~~~~~~~~~~~~~~~

    class  __EXPORT_TYPE class1 {
    public:
        char * func1 (char * aParam1);
        char * func2 (char * aParam2);
        char * func3 (char * aParam3);
    private:
        char * func3 (char * aParam4);
        char * func4 (char * aParam5);
   }

As there is around 100 functions to implement, it would nice to implement these in different .cpp files.
I've tried to declare them as "extern" in the class1 definition although the compiler does not seem to like this.

hope you can help.


Cheers,

weslondon

weslondonAsked:
Who is Participating?

[Product update] Infrastructure Analysis Tool is now available with Business Accounts.Learn More

x
I wear a lot of hats...

"The solutions and answers provided on Experts Exchange have been extremely helpful to me over the last few years. I wear a lot of hats - Developer, Database Administrator, Help Desk, etc., so I know a lot of things but not a lot about one thing. Experts Exchange gives me answers from people who do know a lot about one thing, in a easy to use platform." -Todd S.

bcladdCommented:
You have already separated the header from the implementation file, right? All you need to do is write the appropriate implementation files and tell the compiler they are all required for the object to be built. This is a dependency/linking problem rather than a C++ problem:

(1) There is no need to extern the functions because they are not external IF you link all of the .cpp implementation files into the DLL

(2) The declaration of the functions is already separate from the definitions so no client of class1 needs to care about how you structured your source code.

Hope this helps,
-bcl
0

Experts Exchange Solution brought to you by

Your issues matter to us.

Facing a tech roadblock? Get the help and guidance you need from experienced professionals who care. Ask your question anytime, anywhere, with no hassle.

Start your 7-day free trial
jkrCommented:
bcladd is right - no need to specify them as "extern". You basically would

------------->8-------------------------------

// header.h

   class  __EXPORT_TYPE class1 {
   public:
       char * func1 (char * aParam1);
       char * func2 (char * aParam2);
       char * func3 (char * aParam3);
   private:
       char * func4 (char * aParam4);
       char * func5 (char * aParam5);
  };


------------->8-------------------------------

// functions1.cpp
#include "header.h"

char * class1::func1 (char * aParam1) {
}

char * class1::func2 (char * aParam1) {
}

------------->8-------------------------------

// functions2.cpp
#include "header.h"

char * class1::func3 (char * aParam1) {
}

------------->8-------------------------------

// functions3.cpp
#include "header.h"

char * class1::func4 (char * aParam1) {
}

char * class1::func5 (char * aParam1) {
}


0
It's more than this solution.Get answers and train to solve all your tech problems - anytime, anywhere.Try it for free Edge Out The Competitionfor your dream job with proven skills and certifications.Get started today Stand Outas the employee with proven skills.Start learning today for free Move Your Career Forwardwith certification training in the latest technologies.Start your trial today
C++

From novice to tech pro — start learning today.