Hm, just wrote up an explanation[0] of BQN's high-rank searching, which is the same concept used in J and APL and turns into rank-sensitive search in K. The issue it addresses is that in array programming you'd like to search for each of an array of elements all at once, but this is hard to distinguish from just searching for the array itself. So you look at the entries of the array you're searching to see what rank…
This is my first encounter with K, and it looks absolutely bonkers. The amount of logic you can express in a few characters is mind boggling. However, it makes my brain hurt. Is this a paradigm that becomes intuitive once you learn it, or is it like Ruby in the sense that it’s so flexible that every developer uses their own custom DSL and onboarding is like solving an infinite series of brain teasers?
If anything, K is the opposite of a language where everyone disappears into DSLs- you can write expressive code without wrapping it in custom abstractions. An anti-lisp, if you will. It's not uncommon for K programmers playing with a puzzle to independently arrive at character-for-character identical solutions.