miniblog.

ASTs typically discard comments, and that's usually what you want. The only time (AFAICS) that preserving comments is useful is for writing a code formatter. Could you write a formatter in terms of a list of lexemes? A CST is a non-trivial bit of code for one use case.

Underrated perk of JSON: it's easy to programmatically make changes to a file made by a human. Very few other formats have this advantage. `cargo add` took a bunch more implementation work than `npm install`, because preserving TOML comments takes more work.

Showing lines of context is a remarkably hard problem for a syntactic diff. Line 23 on the right is new, but lines 24 and 25 also map to the same line on the left! Initially I thought this was a bug. It's impossible to show exactly N context lines whilst preserving alignment.