That's indeed surprising. The main site of the organization (not sure what to call them) does show the history and relationship to Iverson, APL and J: https://kparc.io/
"Most programmers will agree that this expression makes perfect sense, but if you show it to a math guy, be ready to hear "no, it isn't". And once you see what makes him think that way, you will also see why we assign values with : in k."
This is pretty dumb. Show "x : x + 1" or even "x : y + 1" to a math person and they will not know what you mean either. There is a non-universal convention in math of using a "defining semicolon" with equals signs, so you could say "x := y + 1" and math people would probably interpret it the same way you do, though they might not like "x := x + 1".
But all this is irrelevant anyway: Progamming is not math. Other parts of the syntax of k don't look very mathy either. Preferring ":" over "=" or something else for assignment is a choice on the part of the language designers, but it has nothing to do with not confusing poor mathematicians.
This looks really cool but what is the real use case for it? If I have no graphics, no easy way to serve HTTP resources and no other weird/niche use cases, what can I use k for outside of academic and financial applications?
Don't get me wrong I think this looks very interesting and I'd love to use it but I wanna use it for real software and I don't see how k makes that easier for me compared to popular widespread languages.
