bash:

$ for str in 1 2 3 4 5
> do
> echo $str
> done
1
2
3
4
5
$                 ← ここでCtrl-P
$ for str in 1 2 3 4 5; do echo $str; done

irb:

irb:0> [1,2,3,4,5].each do |str|
irb:1* puts str
irb:1> end
1
2
3
4
5
=> [1, 2, 3, 4, 5]
irb:0>                 ← ここでCtrl-P
irb:0> end

このへんがうんこ