Lark VS dmd

Lark supports, and recommends, writing and storing the grammar in a .lark file. We have syntax highlighting support in all major IDEs, and even in github itself. For example, here is Lark's built-in grammar for Python: https://github.com/lark-parser/lark/blob/master/lark/grammar...

You can also test grammars "live" in our online IDE: https://www.lark-parser.org/ide/

The rationale is that it's more terse and has less visual clutter than a DSL over Python, which makes it easier to read and write.

First, let me introduce myself. My name is Erez. You may know some of the Python libraries I wrote in the past: Lark, Preql and Data-diff.

It's not super maintained but you might enjoy building something with ppci, Pure Python Compiler Infrastructure. It has some front-ends and some back-ends. There's also PeachPy for an assembler. People like using Lark for parsing, I hear.

lark, a parsing library where I am somewhat involved has a really nice solution to this: Rules starting with _ are inlined in a post processing step.

Lark is a good library to assist with this.

If I may ask, did you consider Lark, and if so, why wasn't it fit for your purposes?

A grammar provides the high level constructs you need to define the "shape" of your data, and it largely takes care of the rest. Grammar libraries exist in other language (eg. lark or Parsimonius in Python) and they weren't created just to make XML parsing easier.

I made a solid attempt at an Earley parser framework of my own, but apparently to get the most reliable performance from Earley parsing you need to implement Joop Leo's improvement for right-recursive grammars, which nobody has been able to adequately explain to me. I've read Kegler's open letter to Vaillant, I've tried to read other implementations, I've even tried to beat my head against the original academic paper, but I don't have the background knowledge to make sense of it all.

Here's the pipeline spitting out the same error as on my macbook did.

https://github.com/dlang/dmd/actions/runs/8023469412/job/219...

Not completely on topic (if you read TFA) but my favorite Git commit is by compiler badass and HN frequenter, where he checks in an entire C compiler to the D language repo:

https://github.com/dlang/dmd/pull/12507

https://news.ycombinator.com/item?id=27102584

A new generated code alone is 4000 lines long [1]. The actual code added is just 2000 lines, and some are used to pay debts, I mean, to make a proper code generator (which can be alternatively written in a simpler scripting langauge). In any case it is never comparable to the entier C parser proper.

[1] https://github.com/dlang/dmd/pull/15307/files#diff-3677bcc89...

D is completely opensource already (https://github.com/dlang/dmd). The "open" of OpenD is just ADR saying that OpenD will be more open to new language features than D has historically been.

The reference compiler, DMD, is open source: https://github.com/dlang/dmd

But they don't accept just any Pull Request or features the community submits, understandably. There's a process called DIP for language improvements: https://github.com/dlang/DIPs/blob/master/DIPs/README.md

However, by some accounts, it's really hard to get anything through.

Given D already has so many feature, I find that to be a good thing , to be honest, by not everyone agrees, of course.