pub type PFNGLPROGRAMUNIFORM1IEXTPROC = Option<unsafe extern "C" fn(program: GLuint, location: GLint, v0: GLint)>;
enum PFNGLPROGRAMUNIFORM1IEXTPROC { None, Some(unsafe extern "C" fn(_: u32, _: i32, _: i32)), }
No value.
Some value of type T.
T