pub type PFNGLSECONDARYCOLOR3IEXTPROC = Option<unsafe extern "C" fn(red: GLint, green: GLint, blue: GLint)>;
enum PFNGLSECONDARYCOLOR3IEXTPROC { None, Some(unsafe extern "C" fn(_: i32, _: i32, _: i32)), }
No value.
Some value of type T.
T