Inno Setup Unknow Filename Prefix

Question

I'm trying to set the output folder of the compiled installer to the desktop. This script can be runned by multiple people across multiple computers, that's why I need to use a dynamic script.

OutputDir= "{#Desktop}"

I'm able to use the prefix userdocs: but not userdesktop:.

//Works:
#define Path "userdocs:Visual Studio 2013\Projects\"
//Throws "Unknow filename prefix userdesktop:"
#define Desktop "userdesktop:";

Here is the documentation:

{userdesktop} & {commondesktop} *
The path to the desktop folder.

{userdocs} & {commondocs}
The path to the My Documents folder.

I also tried commomdesktop: with no success.

Answer 1

In that case you may want to use ISSI and its Constants.

#define ISSI_IncludePath "..\Inno Setup 5\ISSI\" ;path to ISSI
#include ISSI_IncludePath+"\_issi.isi"

[Setup]
OutputDir={#ISSI_myUserDesktop}