Not entirely analogous but you can sort of do a lot of this today with the very programming platform that the HN implementation uses: Racket. And yes with Rack

Not entirely analogous but you can sort of do a lot of this today with the very programming platform that the HN implementation uses: Racket. And yes with Racket you can mix and match languages and create them with out parenthesis (https://docs.racket-lang.org/guide/languages.html https://docs.racket-lang.org/guide/languages.html). BTW the "if" in Python is very different to the "if" in lisp as one is a statement and the other is an expression. I'm curious how the OP plans to deal with the expression != statement.