It is not possible to do a simple iteration over directories in 
@safe mode.
Really? I have to resort to unsafe??
//----
module test;
@safe: // nope. no can do.
import std;
void main()
{
     auto dFiles = dirEntries("", "*.{d,di}", SpanMode.depth);
     foreach(d; dFiles)
         writeln(d.name);
}
//----