pub type PFNGLGETCOVERAGEMODULATIONTABLENVPROC = Option<unsafe extern "C" fn(bufsize: GLsizei, v: *mut GLfloat)>;
enum PFNGLGETCOVERAGEMODULATIONTABLENVPROC { None, Some(unsafe extern "C" fn(_: i32, _: *mut f32)), }
No value.
Some value of type T.
T