Overloading a function like this

[Koedoe]

Here is my code - can anyone pls tell me why my compiler won't allow me to do this?

class TMyClass
{
  public:
    Ansistring Message();
    char* Message();
  
  private:
    AnsiString sMessage;
};

my compiler won't allow me to overload Message() like this. Why?
(I use Borland C++Builder 5.0)

[MrWizard]

What's the actual error

[ErionD]

Ansistring Message();
char* Message();

Isnt this double declaring?

[billholm]

You can't overload a function by just changing their return types.
You have to modify the types of your function arguments.

Ansistring message();
char *message();

is equivalent to

Ansistring message(void);
char *message(void);

This is illegal so the compiler won't allow it.

You have to modify it to something like this:

Ansistring message(Sometype myvariable);
char *message(char myvariable);

or

Ansistring message(Sometype myvariable);
char *message(Sometype myvariable, int variabletoo, char hehe);

Just as long as your function parameter types are not that identical.

[Koedoe]

I know that - but why is it illegal?

Thanx for the reply though.

[SilentStrike]

Because the compiler can't determine which one to call based on the return type, doing so would be extremely error prone when it isn't absolutely impossible.

So either change the function name or the functions parameters.

[Magos]

Originally posted by Koedoe
I know that - but why is it illegal?

Thanx for the reply though.

Because when you run the function Message(void) the compiler has two functions to choose from, and he doesn't know which one to take. This is illegal and illogical.
If the functions have different argument lists, then it knows which one to pick.

[Koedoe]

I know that the compiler mangles the function names using the argument lists - why doesn't it just include the return type in the mangled name?

[Magos]

Originally posted by Koedoe
I know that the compiler mangles the function names using the argument lists - why doesn't it just include the return type in the mangled name?

Because C isn't strictly typed as compared to Ada . You can return a char but store it in an integer variable.