Re: Reliable after-change-functions (via: Using incremental parsing in Emacs)

[Dmitry Gutov]

On 31.03.2020 16:14, Eli Zaretskii wrote:
> Why does it need the entire buffer up front? that sounds like a
> potential performance killer.  Fontifying a small part of a buffer
> doesn't need its entire text.

Because the end product of parsing the buffer is an AST, and the author 
decided to minimize the odds of problems that come with 
incomplete/broken ASTs.

The previous (first) discussion of TreeSitter has an URL to a 
presentation video. You can give it a watch.

Regarding performance, their solution is to make first parsing as fast 
as possible, and updates to an existing AST faster still.

As for the difficulty of sending the whole buffer contents... maybe VS 
Code and Atom somehow make it easier? If so, someone should investigate 
why it has to be slower in Emacs.