Your comments needed. Argument Identifiers.

I'm writing a library that uses printf style format identifiers to identify var arg types. Currently I've got the following list of identifiers. I was wondering if anyone had any suggestions about changing any of them.

Code:

'd' = 4 byte integer (should this be i)
'u' = 4 byte usigned integer
'e' = double (should this be d)
'B' = BSTR
'b' = BOOL
'v' = VARIANT
'S' = LPWSTR
's' = LPSTR
'o' = IDispatch * object
'O' = IUnknown * object (should this be U)
't' = time_t
'T' = SYSTEMTIME * (what should this be)
'D' = DATE (Variant Date)
'f' = FILETIME *

I need to add LPTSTR which will use 'T' so what should I use for SYSTEMTIME? Do you think these identifers would be obvious, it's hard to tell when I have been using them for so long.

Thanks for your suggestions.

I don't see any issues with those identifiers. If other people are to use this function, they will have to learn the new format (ie different from printf's) anyway, so it doesn't really matter what you put. It would of course be best to keep all the printf ones the same, to make learning easier. But remember, there are at least 52 characters to choose from, so you have plenty of room to move.

If you implement a screen output function, I guess you'll be using a printf() style one ey. Personally, I prefer the ease of stream objects. Maybe you should implement the library as a class or set of classes, that way you could use both streams and old school functions. Eg:

Code:

class clsOut
{
public:
	print(LPCTSTR,...); //or however the arg list is done, I forget now
	clsOut operator << (char *);
	clsOut operator << (int);
	clsOut operator << (SYSTEMTIME);
};

Dunno, just a thought.

Thanks for the ideas! I ended up choosing 'W' for SYSTEMTIME.(for Windows time). I've kept 'd' and 'e' for similarity to printf as you suggest. As for the classes, the library is in C, and I can't yet write C++(I can read it, I should learn to write it sometime) so that will have to be a future project.