I couldn't live without ScopedTypeVariables. For me it's an essential tool
when I want to figure out
1. if the type being inferred is the one I expect
2. what type a specific thing in code I am working with is
Also useful for adding that one bit the inferer is missing without
immediately modifying a complex type sig. I can do that later, but the
proof of concept should be quick and easy.
Backwards compat: Isn't this what we have Haskell 98, Haskell 2010, etc?
On Sat, 5 May 2018 04:35 Anthony Clayden,
This thread is a discussion about discussions, not the discussion itself ;-)
I'm cc'ing to the cafe; but I'd prefer replies to come to glasgow-haskell-users.
I can volunteer to at least scrape together all the objections to ScopedTypeVariables as currently. It's not yet a proposal, so not on github. Start a wiki page? A cafe thread? (It'll get lost.) A ghc-users thread? (It'll get ignored.)
... don’t care what forums or list or whatever. As long as it’s
collated and such > It could even be on the prime issue tracker for prime proposals. Just that it’s written down :)
Thanks Carter, but I understand Haskell Prime to be to assess mature/stable proposals (preferably already delivered as extensions). This discussion is at first going to be more exploratory: * likes and dislikes about ScopedTypeVariables as currently. * confusions experienced by users (especially newbies) -- although absolute newbies wouldn't be using it(?), so intermediates? * feedback from those teaching Haskell. * wild ideas for possible alternative designs. * possible improvements to the current design. * I think we're all agreed that ScopedTypeVariables should have been in Haskell from the beginning; but it wasn't, so now we have to worry about backwards compatibility for programs that worked around the omission. Or do we? What code would break? How much pain would that cause? * anything else?
We have lots of forums, but your point is that certain sorts of discussions never get going with the right audience – you especially point to “confused beginners”. ... It’s quite a challenge because beginners tend not to be vocal, and yet they are a crucial set of Haskell users. Every Haskell user started as a beginner.
On this particular topic, there's plenty of confused people asking questions on StackOverflow. (Heads up: they're especially asking why they need explicit `forall` whereas in reguar Haskell that 'intermediates' see, the forall is implicit.)
Can other people point me to questions/likes/dislikes on other forums? Reddit for example.
If you've read this far, you now understand what we're trying to cover. It's going to be random/varied thoughts at first, then perhaps coalescing to an approach or two. At that point a formal proposal on github proper; and the random stuff might be interesting background but will essentially get archived/thrown away.
I do agree with David's suggestion that github Issue tracker looks like a suitable solution. We can write formatted code and text. We can add links and references. What do others think? Joachim has opened up Issues tracker, as a try-out. If using it doesn't work out, that's fine and in keeping with my "thrown away" above.
Also where else should I post links to this message to 'advertise' the thread? I don't reddit much, so if that's suitable, please someone post there.
Thank you AntC _______________________________________________ Glasgow-haskell-users mailing list Glasgow-haskell-users@haskell.org http://mail.haskell.org/cgi-bin/mailman/listinfo/glasgow-haskell-users