[eru]

I prefer recursion over loops. But even more I prefer abstracting away the recursion into combinators.

One of my favourite combinators is matrix multiplication. You define what 'addition' and 'multiplication' mean in your case, and all of a sudden you get an algorithm that computes shortest paths in a graph or does regex matching. See https://news.ycombinator.com/item?id=9751987

But for more bread and butter cases, there's 'map' over various data structures, and 'reduce' and traversals of trees etc.

[aeonik]

I'm forbidden from those links :(

[eru]

Oh, that's a shame. However, if you do a websearch for 'fun with semirings' you can find the relevant publication. Or you can use the wayback machine or so?