Spitfire is a new error tolerant parser for Elixir.
The goal of the project is to make it easier for editor tooling to provide code intelligence for incomplete snippets of Elixir code.
- Parse all Elixir Syntax into core compatible AST.
- Error tolerance
- Environment querying API
It is not clear yet the scope of Spitfire, but at a minimum it will be an independent parser and library.
For more information, please see elixir-lang/elixir#12645.
The project is a handwritten Pratt parser (a type of recursive descent parser). A hand written parser allows for better error tolerance as well as (hopefully) better error messages.
Pratt parsers are becoming very popular in the realm of error tolerant parsing. Projects that I have been watching and learning from include the rustc parser as well as the new Prism parser for the Ruby project.
Now that phase 1 (parse all Elixir syntax) entering the final lap, contributions should be easier.
The goal is to test Spitfire against popular repos and see if there are any differences in the output.
This can be easily accomplished by cloning the project and running the bin/ci script from the Spitfire repo.
bin/ci path/to/projectThis will attempt to parse and test equivalence for each file in lib/ of that project and print out any differences that it finds.
Then you simply make a minimal unit test for that problem, fix it, open a PR!
I'd like to thank Thorsten Ball, the author of Writing an Interpreter in Go. I read this book a couple of years ago and built out the language from the book. Thorsten teaches you how to build a Pratt parser, which is really proving helpful for the development of Spitfire.
MIT License
Copyright (c) 2023 Mitchell Hanberg
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