[Proposal] Naming for iter

[hackwaly]

as_iter -> iter iter -> for_each

[1, 2, 3, 4, 5]
  .iter()
  .for_each(fn { it => print(it) })

[bobzhang]

iter each ?

[shamiao]

vote .iter() & .each(f). This allows the term 'iter' indicates @iter.Iter types without ambiguity.