overridable parser

[jam01]

Allow the ability to provide a different parser

[He-Pin]

Seems it's been used in https://github.com/jam01/xtrasonnet

[jam01]

Hey! Docs added.

I'm the author of xtrasonnet and I don't currently make use of a custom Parser there, but I have written one that I'm hoping to use. I'm maintaining a clone of sjsonnet where I add a couple of operators, but I think this feature fits cleanly in the project as it doesn't deviate from the jsonnet spec.

The work you all have done to modularize std and add extension libraries will make the xtrasonnet code sooo much cleaner, I was doing some hacks in order to provide another library than std.

Looking fwd to 1.0.0 release!

[He-Pin]

I think the ? and ?? are quite nice, you may upstream it here, and enable that behind a parserSetting of sjsonnet. wdyt

We are using this sjsonnet at work too

[jam01]

You're using my fork at work?

I'd have to think of exactly how to feature flag it in the parser, but I'm happy to give that a try if it'd be welcome.

[He-Pin]

  private def variableResolver(name: String): Option[Expr] = {
    if (name == "tb" || name == "$tb") {
      Some(FunctionRegistry.module)
    } else {
      None
    }
  }

@jam01 Yes, I have something like this, to have tb redirect to our extensions, and I think it should be xtr in xtrasonnet.

[jam01]

Yes! I'm definitely switching to using this as soon as 1.0.0 goes live. Hopefully soon!

[jam01]

I'll defer the ?? and ?. operators for another PR because those cut across Parser, Expr, Optimizer, and Evaluator.

So please consider merging this in independently if it's OK.

Out of curiosity, is 1.0.0 expected to be released soon?

[He-Pin]

@jam01 I think only @stephenamar-db can tell you this:)

[stephenamar-db]

I'm very focused on getting the current version (0.5.6) imported inside Databricks. Once this is done and stable, then I'll resume work on wrapping up 1.0.0.
Probably sometime in November I guess

[He-Pin]

@jam01 I think you need rebase this.

[jam01]

Formatting wasn't cooperating before, should be all good now.