[jbmorgado]

What I don't understand is why do we still use TextMate grammars.

Can anyone explain why this is the case? It's not only in VSCode, I remember seeing something about TextMate grammars also in other editors.

[trishume]

Copy-pasted from a comment I made elsewhere:

It's harder than it sounds if you want to support many languages. The Sublime syntaxes repo I use has 34,000 lines of grammars whereas my engine is only 3000 lines of code. If you count all the tmLanguage files for nice languages available online it's probably hundreds of thousands of lines, and that's in a pretty dense format. The whole point of using tmLanguage files is that people don't care about how fast other languages are if there is no highlighting for their language. I could get way better performance by rewriting all those grammars using compiled parsers in Rust (like Xi has as an option https://github.com/google/xi-editor) but it would take an absurd amount of effort.

[jbmorgado]

Thank you, that explains a lot, but now a new doubt came from it:

Why don't we use other text editors grammars that are simpler/quicker to parse in JS? I have no idea on the technicalities, but for instance, Vim or Emacs grammars instead?

[okdana]

I can't speak to Emacs, but i know that Vim's syntax definitions are (a) not as powerful as TM's, (b) a nightmare to maintain, and (c) heavily reliant on features specific to Vim's loony regular-expression engine (like variable-width look-around).

My experience is that most syntax highlighters and their definition formats (Scintilla, nano, almost anything that's based on JavaScript) are very limited/naïve compared to TextMate's. It doesn't have to be that way -- TM can certainly be improved upon -- but it is.