Month: August 2011

James Noble

Grace events at SPLASH

We’re now planning the next Grace workshop(s) in Portland Oregon in conjunction with the SPLASH conference. Based on the successful ECOOP workshops, at this stage we’re thinking of holding:

  • a BOF on Monday Oct 24 in the evening — after the Educators’ Symposium, the Dynamic Languages’ Symposium, PLOP, and the workshops (including Plateau & FOOL) which are on Sunday and Monday. All three of us will be there for a general report-back on the project to date.
  • a Design Workshop on Friday Oct 28th (the day after the conference) working over open questions in the design in detail (probably the module & type systems). This will be held at Portland State University, an easy tram ride from the conference venue & hotels. We expect some people would stay only for the morning, others till mid-afternoon.

We’d love to see as many of you as possible at the BOF and at design
workshop. If you’re able to come, please let us know by emailing
James, kjx@ecs.vuw.ac.nz, so we have some idea who’s coming.

Alternatively, if there is are reasons why the proposed dates don’t
work — but other dates might — again let us know!

Andrew & James will be around for all SPLASH, so we’ll also be able to catch up then. We’ll probably arrange to go out for dinner on the Thursday evening after the conference (before the Friday workshop), and we can probably organise another BOF during the conference if many people can attend neither Monday nor Friday.

We look forward to catching up with everyone at SPLASH/OOPSLA this year, and hope may of you will be able to come to the BOF and the workshop.

cheers

Andrew & Kim & James

James Noble

From Lancaster to Portland

So this is a belated message about the Grace meetings in Lancaster. Early during the week (Tuesday evening) we held a BOF – mostly hosted by Kim – with a good group of people attending to hear about Grace. There were good discussions and questions, mostly about where we plan to go next. I wish I could have stayed for the whole thing!

Then on the Saturday, after the conference – while most people were heading home – Gary Leavens (University of Central Florida), Erik Ernst & Johan Winther (Aarhus Universitet), and Kim & James met for a “good, intense, and productive” time to talk over the next stages in the design – primarily the type system. Main choices so far include:

  • A primarily gradual, parametric, structural type system
  • Classes, Types, and Methods may all take generic parameters
  • Generic types written as Array[T], following Eiffel and Ada.
  • Constraints on type parameters expressed via where clauses, following CLU & C#
  • Explicit union types e.g. (ListNode[T] | None) designed to work well with Grace’s pattern matching. These are inspired more directly by ML-style languages (& Ceylon) as an alternative to Scala’s case classes; although (as in general in Grace) they will remain primarily structural types
  • No need for variance annotations — an ad-hoc structural interface can always be defined where necessary
  • MyType and exact types at the top language level

Over the next few weeks – now we’re over the jetlag! – we hope to post on more details of this design, and eventually a 0.2 version of the language spec.

And although we’re just back from Lancaster, we also need to look forwards to the next time we’ll meet about Grace, which we’re planning at the SPLASH conference in Portland (Oregon) at the end of October. Our current thoughts are a general BOF early in the week (perhaps Monday evening) with a day-long design working session perhaps the Friday after the main conference ends.

We still have a little time to confirm these plans – if you’re thinking about going to SPLASH, we’d love to hear from you, so let us know when you’d be able to come along.