Tree-sitter for liblouis tables

A Tree-sitter parser for liblouis tables.

This can serve as a way to support structural editing, syntax checks and highlighting for liblouis braille tables in any editor that supports tree-sitter (currently Atom, possibly neovim and Emacs).

It can also be used as a basis for a parser for the liblouis tables although personally I would prefer a Rust native solution such as nom or pest.

Install

npm install tree-sitter-liblouis

Build

npm install
export PATH=$PATH:./node_modules/.bin
tree-sitter generate

To run the test suite

tree-sitter test

Usage

Parsing

tree-sitter parse '/path/to/liblouis/tables/*' --quiet --stat

To get the syntax tree for a particular table

tree-sitter parse /path/to/liblouis/tables/nl-NL-g0.utb

You can even get an XML export of the syntax tree

tree-sitter parse /path/to/liblouis/tables/nl-NL-g0.utb --xml

For more info consult the help with tree-sitter parse --help.

Highlighting

You can use tree-sitter to highlight the source code of a liblouis table. You need to set up your per-user configuration for this to work.

tree-sitter highlight ~/src/liblouis/tables/da-dk-g28.ctb

Again, consult the help with tree-sitter highlight --help. You can for example generate a highlighted HTML document

tree-sitter highlight ~/src/liblouis/tables/da-dk-g28.ctb --html > da-dk-g28.html

To get feel how this looks using the standard theme look at the generated da-dk-g28.html.

Status

As of this date the parser handles all liblouis tables except for ja-kantenji.utb and ko-chars.cti. There seems be a problem with some Hangul and Han characters.

I had hoped this would be immediately applicable in a wide range of editors. But it appears that not that many support tree-sitter yet. Emacs has a tree-sitter package. But it still needs some manual tweaking to make it recognize the liblouis tree-sitter.

Acknowledgements

The grammar is pretty much just a port of the EBNF grammar in rewrite-louis, which in turn is a just port of the Parsing expression grammar from louis-parser.

License

Copyright (C) 2021 Swiss Library for the Blind, Visually Impaired and Print Disabled

Permission to use, copy, modify, and/or distribute this software for any purpose with or without fee is hereby granted, provided that the above copyright notice and this permission notice appear in all copies.

THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.