alt Hacker NewsAt first brush, everything about this sounds like overly ambitious vapourware. Is there a reason to think this is going to deliver? People involved, what's already shipped, etc?
I particularly loved this from their roadmap:
> Completed
> Shift operation
> Enables LR parsing of expressions like 2+2
Being able to parse 2 + 2 is definitely good!
And their thoughts on testing:
> How our project reaches production stability is a process that often surprises people. We don't write a lot of tests for example, and we often don't do much testing before we ship releases. Instead we test exhaustively after we ship releases, which is the only way we know of knowing for sure that the product we shipped does what we think it does. [...] We also don't (usually) practice TDD. If you look at the number of tests we have, it likely won't seem like it's anywhere near enough to keep a project of this size stable! The secret sauce here is that our key invariants aren't written in our test files, they're baked into the core of the implementation. Every time you use the code, you're essentially testing it. To gain confidence in our core, we simply try to use it to do a lot of real work.
Man, why did i not think of that, i could have got out of writing so many tests if i'd just baked the invariants into the core of the implementation!
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In this case the tool is meant to parse programming languages, so once I write some parser grammars every valid code file in existence is a test case. Seen that way I have more test cases than I know what to do with.
We've come a ways from 2 + 2. This week my goal is to feed our own whole codebase through the JS parser, and I should be able to. I managed to parse a few hundred lines of real JS last week before running into Automatic Semicolon Insertion trouble that I needed to tinker with the core to fix.
While I get that our low profile smacks of vapor, we actually have working packages published: bablr and @bablr/cli. I'd consider them to be beta quality right now, having gone through many previous releases that I'd only consider alpha-quality, and even more releases before that.
It's not too hard to verify my central claim here which is that we're giving away what they charge money for. Their serialization format is secret, proprietary. Ours, CSTML, is open: https://docs.bablr.org/guides/cstml. Their free product make you re-parse the entire project with every code change you make. Ours is built with copy-on-write immutable data structures so that you can always build new things without losing old ones. Our way you can compose fragments of trees together with new code into new trees like you're playing with lego bricks.