pub type OPENSSL_sk_delete_if_func = Option<unsafe extern "C" fn(obj: *mut c_void, data: *mut c_void) -> c_int>;
enum OPENSSL_sk_delete_if_func { None, Some(unsafe extern "C" fn(_: *mut c_void, _: *mut c_void) -> i32), }
No value.
Some value of type T.
T