miniblog.

Over a sufficiently long time horizon, all code you write is legacy code.

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.

I'm intrigued to see that Google has quantified that new code is generally buggier and less secure than code that has existed in your codebase for longer: https://security.googleblog.com/2024/09/eliminating-memory-safety-vulnerabilities-Android.html