std::string debug function

[NLscotty]

Hello,

I'm trying to write a debug functions for my application so I can see all the values I like to.

My goal is it looks like this:

void Debug(std::message, ...)

So that I can call it like this:

Debug("Error: %i, %i", 34, 35);

I've no idea how I can work with %i, or if there are better solutions.

This is what I've so far (not much), just a basic idea:

void Debug( std::string message, ...)
{
        va_list list;

	va_start(list, message);

	  ??? va_arg(list, ??  );

	va_end(list);
        // here message shoul contain everything and be ready for output ? 
	cout << message << endl;
}

Greetz

[D_Drmmr]

Why not just forward the call to sprintf / fprintf?

[Paul McKenzie]

Hello,

I'm trying to write a debug functions for my application so I can see all the values I like to.

My goal is it looks like this:

void Debug(std::message, ...)

That code is ill-formed. For a function that has ellipses (...), the argument to the left of the ellipses must be a POD type. So forget about it.

Use sprintf(), std::ostringstream(), or boost::format from the boost library.

Regards,

Paul McKenzie

[Ejaz]

Is this what you are looking for?

#include <iostream>
#include <Windows.h>

inline void Trace( const char* format , ... )
{
#ifndef NDEBUG
	char buffer[ 0x400 ];
	va_list  fmt_list;

	va_start( fmt_list, format );
 	vsprintf_s( buffer, 0x400, format, fmt_list );
	va_end( fmt_list );
 	strcat_s( buffer, 0x400 ,"\n" );

	// ::OutputDebugString( buffer );
	std::cout << buffer;
#endif // NDEBUG
}


int main()
{
	Trace( "Error: %i , %i" , 34 , 35 );
}