greetings, Robert. thank you, it does make sense to me.

> >> res=[]; 0.step(a.length - 1,2) {|i| res << [a[i],a[i+1]]}; res
> => [[0, 1], [2, 3], [4, 5], [6, 7], [8, 9]]

i know that an yieldee is 100% passive to its yielder, but i often feel
desire to let it fetch to the next/previous yielded object from inside
the yieldee.

don't you know any cool way to do this in ruby?

-- 
<name species-designation="5618" default-lang="ja_JP">SHIGETOMI,Takuhiko</name>
<contact medium="email">tshiget1 / gw.nsw.co.jp</contact>
<location federational-alias="/galaxy/alpha-quadrant/sector-001/earth/">
  /void/3d/universe/milkyway-galaxy/orion's-arm/sol-solar-system/3rd-planet/fareast/jp/tky/
</location>
<hail>resistance is futile.</hail>