Re: cc-mode fontification feels random

[Perry E. Metzger]

On 7/11/21 14:12, Stephen Leake wrote:
> The ELPA package wisi provides a parser-based fontification engine,
> which makes things like this more consistent. It is currently used for
> ada-mode. Note that syntax errors in the source can cause bad
> fontification, but the wisi parser has very robust error-correction, so
> it usually does a good job even with syntax errors.
>
> However, parsing C and C++ is complicated by macros; wisi makes no
> provision for that.
>
> Another option is an LSP based system via the EPLA package eglot; that
> delegates fontification to the language server. I don't know how well
> the C/C++ language servers perform for this.

Using LSP for fontification is unfortunately not sufficiently high 
performance. LSP is really intended for things like providing type 
information or enabling refactorings.

I note that several other modern editors now make use of the "Tree 
Sitter" library (see https://github.com/tree-sitter/tree-sitter ) which 
was designed explicitly to provide a C library for incremental 
programming language parsing for text editors. It allows for very 
consistent fontification in other editors like Atom, and is available 
under the MIT license, which would permit it to be included in Emacs.

A very good presentation a few years ago by the author, including an 
explanation of how Tree Sitter enables high quality fontification in 
editors like Atom, can be viewed on youtube: 
https://www.youtube.com/watch?v=Jes3bD6P0To

Perry