Optionad dll parameters

[JohnOne]

Is it possible in some way to make parameters optional in an exported C++ win32 dll?

Kind of (this does not work) 

int func(LPCTSTR param1, LPCTSTR param2 = L"param"){
    //stuff
    return 0;
}

Or something similar, I know it's a long shot cause find find anything to suggest there is.

[JohnOne]

Or perhaps be overloaded in some fashion I'm unaware of?

[GtaSpider]

Whats the matter?

void func( int required, int optional = 0);

 

Should work with C++ (not with C)

[JohnOne]

Does not work, crashes without error (Well OS error with option to close, wait or check online) when called from AutoIt.

EDIT:

That's fine for internal function but I've not been able to get it to work externally.

Edited February 14, 2014 by JohnOne

[funkey]

Afaik you cannot use optional parameters in DLLs. This is because the C++ compiler handles the optional parameters at compile time. So if you compile a DLL there is no optional parameter possible. But you just can use AutoIt for using optional parameters in your UDF.

[JohnOne]

Thanks funkey, you must be correct.

[jaberwacky]

You could go with your overloaded function idea though.

Come to think of it, there must be a better way.  Didn't Jon do it somehow with DllCall?

Edited February 18, 2014 by jaberwacky

[JohnOne]

Cannot judge by native functions, because it's all handled in the interpreter.

Closest I'm going to get is in my other dll thread.

if (!param || !Param[0]){

    //provide a default;

}

[Richard Robertson]

The above is correct. Native functions do not have optional parameters. The headers may indicate default values which the precompiler stage will read and fill in right before compilation.

Example

void method(int parameter = 0)
{
}

int main()
{
    method();
    return 0;
}

// becomes

void method(int)
{
}

int main()
{
    method(0);
    return 0;
}

[trancexx]

I'm not sure what jaberwacky meant, but DllCall doesn't provide way to omit default parameters.