miniblog.

Do commas ever appear in idiomatic Clojure? It's syntactically legal but I don't think I've ever seen them in the wild.

Lisp is the only language I've seen where it's idiomatic to have some locals scoped to the *middle* of a function. It's a consequence of let blocks. It's neat, but I rarely miss it elsewhere. I'm happy with "scoped from here to the end of the block" in e.g. C or Rust.

Arrays being truthy in JS still catches me out sometimes. In Python or Lisp, empty lists are falsey and truthiness is safe and idiomatic.