It's funny how languages can offer multiple forms of syntax, but formatters standardise to a single form.
E.g. single vs double quotes in JS, optional semicolons in JS, different ways of grouping imports in Rust.
Should new languages be more syntactically opinionated?
Do commas ever appear in idiomatic Clojure? It's syntactically legal but I don't think I've ever seen them in the wild.
Diff sliders are a really interesting problem for AST diffs. Here's a surprising example.
At first, it looks like the first `|` should be highlighted. However the first `|` is the outer `match` case, and the inner | is syntactically an or-pattern!
