WebBS VS minipratt

A few years back I had to implement a new parser for a custom expression language to replace an old parser that didn’t giving very good errors and was hard to extend. I never did the traditional CS track so parsers were kind of mysterious black magic so naturally first thing I did was search HN.

I stumbled on an older parsing thread [1] with a link to a toy Prayt implementation [2] made by an HNer… and shamelessly ripped it off to write my own Pratt parser implementation.

Great success! Writing a Pratt parser by hand is a lot easier than I thought and like the comment says, adding type information was trivial.

[1] https://news.ycombinator.com/item?id=24480504

[2] https://github.com/mx-scissortail/WebBS

Some time ago I went down a fascinating rabbit hole on Pratt parsers while writing a math expression evaluator. In addition to the OP and above-linked article, I found the following helpful.

- How Desmos Uses Pratt Parsers (2018) - TypeScript - https://engineering.desmos.com/articles/pratt-parser/ - Source: https://github.com/desmosinc/pratt-parser-blog-code

- Simple But Powerful Pratt Parsing (2020) - Rust - https://matklad.github.io/2020/04/13/simple-but-powerful-pra... - Source: https://github.com/matklad/minipratt