RuPkl: Pkl parser for Ruby

[taichi-ishitani]

Hi,

I'm developing a Pkl parser named RuPkl for Ruby.
https://github.com/taichi-ishitani/rupkl

RuPkl can load a Pkl code string into a Ruby structure like below.

require 'rupkl'

pkl = <<~'PKL'
  // From:
  // https://pkl-lang.org/main/current/language-tutorial/01_basic_config.html
  name = "Pkl: Configure your Systems in New Ways"
  attendants = 100
  isInteractive = true
  amountLearned = 13.37
PKL

RuPkl.load(pkl)
# =>
# {:name=>"Pkl:Configure your Systems in New Ways",
#  :attendants=>100,
#  :isInteractive=>true,
#  :amountLearned=>13.37}

I've confirmted that RuPkl can load Pkl code strings in "Tutorial: Basic Configuration" and released v0.1.0!
https://rubygems.org/gems/rupkl

[holzensp]

This looks fun. The first chapter the tutorial uses almost exclusively Pcf, which is a syntactic subset of Pkl. What's your ultimate goal for this parser? What are you going to do with uninterpreted things (for/when generators, amends clauses, member predicates, etc.)?

[taichi-ishitani]

@holzensp ,
Thank you for your reply!

What's your ultimate goal for this parser?
What are you going to do with uninterpreted things (for/when generators, amends clauses, member predicates, etc.)?

Of cause, the ultimate goal is implementing all features of Pkl.
Next step is enhancing RuPkl to be able to parse Pkl code strings in the 2nd chapter of the tutorial. So I will implement the amends feature.

[holzensp]

A full re-implementation?? Of course, you're more than welcome to it, but I think that's considerably more work than it's worth.

[taichi-ishitani]

Yes, I know. So I'm focusing parsing Pkl code strings in the tutorial for now.

[bioball]

Have you considered writing language bindings for Ruby instead? For details, see our documentation

Pkl is an interpreted language. For a full implementation, you'll need to implement an interpreter, not just parse. If that's your goal, carry on! But note that we don't have a language specification, and there's certain behaviors of Pkl today that will change before we get to our 1.0 release.

[taichi-ishitani]

I'm planning to integrate RuPkl and my Ruby app and I'd like to keep its install flow simply.
Therefore, I'm deolping pure Ruby parser but not language binding.

[taichi-ishitani]

Today, I released RuPkl v0.2.0!
https://github.com/taichi-ishitani/rupkl/releases/tag/v0.2.0

This release includes following new features:

• Support Mapping and Listing structures
• Support amend and new expressions
• Support method definition
• Implement some built-in properties and methods