fn default_extend_tuple_g<G, F, E, D, C, B, A, EG, EF, EE, ED, EC, EB, EA>( iter: impl Iterator<Item = (G, F, E, D, C, B, A)>, g: &mut EG, f: &mut EF, e: &mut EE, d: &mut ED, c: &mut EC, b: &mut EB, a: &mut EA, )where EG: Extend<G>, EF: Extend<F>, EE: Extend<E>, ED: Extend<D>, EC: Extend<C>, EB: Extend<B>, EA: Extend<A>,