CreateWindowExW

Undocumented in source but is binding to Windows. You might be able to learn more by searching the web for its name.
extern (Windows)
HWND
CreateWindowExW
(
DWORD dwExStyle
,
LPCWSTR lpClassName
,
LPCWSTR lpWindowName
,
DWORD dwStyle
,
int x
,
int y
,
int nWidth
,,,
HMENU hMenu
,
HINSTANCE hInstance
,
LPVOID lpParam
)

Meta