C header file: tagged enumerations

[Kagamin via Digitalmars-d-learn]

enum
{
// 12 others ...
	INSTALLMESSAGE_INITIALIZE     ,
	INSTALLMESSAGE_TERMINATE      ,
	INSTALLMESSAGE_SHOWDIALOG
}
static if(_WIN32_MSI >= 500)
enum INSTALLMESSAGE_PERFORMANCE=15;
static if(_WIN32_MSI >= 400)
enum INSTALLMESSAGE_RMFILESINUSE=16;
static if(_WIN32_MSI >= 450)
enum
{
	INSTALLMESSAGE_INSTALLSTART=17,
	INSTALLMESSAGE_INSTALLEND
}