full path to source file __FILE__

[Jonathan Marler via Digitalmars-d-learn]

Is there a way to get the full path of the current source file? 
Something like:

__FILE_FULL_PATH__
I'm asking because I'm rewriting a batch script in D, meant to be 
ran with rdmd.  However, the script needs to know it's own path.  
The original batch script uses the %~dp0 variable for this, but 
I'm at a loss on how to do this in D.  Since rdmd compiles the 
executable to the %TEMP% directory, thisExePath won't work.

BATCH
-----
echo "Directory of this script is " %~dp0


DLANG
-----
import std.stdio;
int main(string[] args) {
    writeln("Directory of this script is ", ???);
}