egison VS cQuents

Look into egison, a "Pattern-Match-Oriented language": https://www.egison.org/

Have a look at Egison. It should be a source of inspiration to anyone doing generalised pattern matching. [_,_/2] ~= [2,1]|[6,3] in particular is even clearer in Egison: $p :: #(p / 2).

I think this is a bad idea. In fact, Egison offers a precedent with a better approach. The offered alternative is strictly more powerful as it allows you to refer to a single subpattern multiple times in a greater pattern, and even marks a computable expression you can use in patterns, allowing code like

Egison language. Research language that does some really neat stuff with pattern matching.

Egison is weird https://www.egison.org -- it takes a single concept (pattern matching) and pushes it as far as it will go.

It's not exactly the high profile type stuff other people are discussing, but when I started on my LangJam language SeekWhence (name is tentative) last week, I was a little surprised to not have come across any other languages that implement mathematical sequences as a primitive, even among the esoteric crowd. The only other one I know of is cQuents, which is heavily esoteric and designed for code golfing, whereas SeekWhence is very much designed as a "general purpose" language (if you can call a Python interpreter hacked together over the course of a week "general purpose").