Hello,
I don't think we should accept this proposal, for the following reasons:
* it is premature to "reserve" syntax for a future extension
* I am not convinced that a design with 12 quantifiers is what I'd want
to use
* I am not convinced about the utility of the "dependent haskell"
extension in the first place.
-Iavor
On Fri, Feb 23, 2018 at 7:39 AM Joachim Breitner
Dear Committee,
this is your secretary speaking:
Dependent Haskell quantifiers were proposed, by Richard. https://github.com/ghc-proposals/ghc-proposals/pull/102 rendered at https://github.com/goldfirere/ghc-proposals/blob/pi/proposals/0000-pi.rst
I’ll shepherd that myself.
This proposal defines and reserves the syntax for the quantifiers that eventually Dependent Haskell will need, and allows their use where it makes sense already (e.g. in Kinds). The quantifier are:
forall a. forall a '. forall a -> forall a '-> foreach a. foreach a '. foreach a -> foreach a '-> ty => ty '=> ty -> ty '->
It addresses the interaction with warning (e.g. -Wcompat). It looks well-thought-through, one might infer that the authors wrote a thesis about this stuff.
There is some syntactic bikeshedding possible; for example the proposal proposes "foreach" instead of "pi" (the latter would make "pi" a keyword, which would be unfortunate for those who deal with circles).
If someone has better ideas, in particular about the use of ' to denote matchable arrows, we still have time to suggest them.
I recommend to accept this proposal in the current form or with further refinements to the syntax, if we can come up with them.
Thanks, Joachim -- Joachim Breitner mail@joachim-breitner.de http://www.joachim-breitner.de/ _______________________________________________ ghc-steering-committee mailing list ghc-steering-committee@haskell.org https://mail.haskell.org/cgi-bin/mailman/listinfo/ghc-steering-committee