Just a note that the most common Markdown flavor (Commonmark) doesn't actually support frontmatter. The author is using presumably Obisidian-flavored Markdown (which is a mixture of Commonmark, GH-flavored Markdown, and Latex). For file-tagging, I would consider TMSU [0] instead of writing bespoke tools. (ideally we would just use xattrs, but the world isn't ready for that) [0]: https://tmsu.org/
I like Commonmark but I wish it would have been more opinionated. They chose to allow two ways to do everything[0]. Making * always be used for bold and _ always for italicizing is so much clearer, and some Markdown flavors (notably WhatsApp) do this. So you only have to do *haha* or _haha_, which also makes italic-bold more _*intuitive*_. Similarly they should have gone with one style of headings, probably with #. T…
> Markdown files are essentially plaintext with some extra syntax for common elements like sections, bullet points, and links. The format deliberately avoids precise control over display details like font selection. Following the rule of least power, I consider this limitation a feature.
One of my biggest ongoing frustrations has been MDX - a sort of markdown-and-JSX mixture whose spec is now in its third release and which has made very little effort to maintain compatibility with either CommonMark or itself. It is fairly strict and fairly elegant, and moving to a new version requires rewriting all previously-written documents to eliminate no-longer-supported syntax and re-training writers. Both of those things are miserable tasks; it has absolutely killed any tolerance I might have had for a stricter parser.