[gjulianm]

> here is an inner one, {x,+/-2#x}, and the outer one (the entire thing

So in the inner one, x is the argument of the inner function or the argument of the outer one? Is x always an argument to anonymous functions?

> / (like a lot of k symbols) does a few different things depending on context

That's a recipe for confusion.

> Sure, there may be some complexities or questions, but there are in all languages

I can go back to the initial example: just browse other implementations of Fibonacci in different languages. For most of them you can actually understand a bit what's happening, even if it's a different paradigm (e.g, I can understand the Haskell or Clojure implementations without too many issues, and in fact I can learn things about the language from that). But operators that do different things depending on context, insistence on non-standard symbols, weird scope issues... That's not "complexities or questions that are in all languages", that's a recipe for confusion and extra complexity that you need to have in mind on top of the complexity of whatever you are coding.

[rak1507]

Default arguments to anonymous functions are x, y, and z. You can also name arguments like this. {[foo; bar] foo+bar} is the same as {x+y}

I'm not denying it is probably more possible to gain a superficial understanding of what code written in other languages does than code written in k to someone who's never seen k before. This just doesn't seem like that important of a language feature. The 'confusion and extra complexity' you mention wouldn't really confuse anyone who'd tried k for more than a couple of hours (at most).