About variadic in functions and dstring type

[Lorenzo Villani]

Hi, I want to modify or extend std.stdio.writefln in order to support (for example) a String object.. i.e.: I would like to be able to do something like that

String s = new String("Hello World");
writefln(s);

I thought that it should be possible by writing some sort of wrapper around the original writefln which scans the _arguments array and if an argument is a String object it does an in-place substitution of the argument to a standard D string type printable by writefln.

Now let's come to my 2nd question: what are dchar and dstring and their differences from char[] (or wchar[]) ?

Thanks in advance
Lorenzo "Arbiter" Villani