Am 22.10.2016 um 14:18 schrieb Rik Howard:
Dear Haskell Cafe Subscribers
on the recommendation of someone for whom I have great respect, I have just subscribed to this list, it having been suggested as being a good place for me to get feedback regarding a project that I have been working on. I am humbled by the level of discussion and it feels to be a very bold step for me to request anybody's time for my words.
The linked document is a four-page work-in-progress summary: the length being stipulated, potential novelty being the other main requirement. Given the requirements, the summary necessarily glosses over some details and is not yet, I fear, completely correct.
It is a programme for designing a programming language. It is leaving out a number of central issues: How to approach modularity, whether it should have opaque types (and why), whether there should be subtypes or not, how the type system is supposed to deal with arithmetic which has almost-compatible integer types and floating-point types. That's just off the top of my head, I am pretty sure that there are other issues. It is hard to discuss merits or problems at this stage, since all of these issues tend to influence each other.
The work arises from an investigation into functional programming syntax and semantics. The novelty seems to be there but there is too a question as to whether it is simply a gimmick. I try to suggest that it is not but, by that stage, there have been many assumptions so it is hard to be sure whether the suggestion is valid. If anyone has any comments, questions or suggestions, they would be gratefully received.
One thing I have heard is that effects, subtypes and type system soundness do not mix well. Subtypes are too useful to ignore, unsound types systems are not worth the effort, so I find it a bit surprising that the paper has nothing to say about the issue. Just my 2c. Regards, Jo