Finding an element by iteration
Since all datastructures in Я are traversable, we can just iterate over it:
[1,2,3,4,5,6,7,8,9] `yokl` Forth `ha` Check `ha` exact 7
For each item we apply a predicate which could interrupt iteration in case we found an item:
exact sample current = Continue `la` Interrupt `li` sample `hd'q` current