pub type PFNGLGETQUERYOBJECTUI64VPROC = Option<unsafe extern "C" fn(id: GLuint, pname: GLenum, params: *mut GLuint64)>;
enum PFNGLGETQUERYOBJECTUI64VPROC { None, Some(unsafe extern "C" fn(_: u32, _: u32, _: *mut u64)), }
No value.
Some value of type T.
T