[ghc-steering-committee] Any future plans for HasField redesign?

[Adam Gundry]

Hi John,

(I'm not on the steering committee, but since you asked about HasField...)

The current status of the draft proposal to which you linked is that I'm 
still planning to finish it off and open a discussion PR, but that it 
needs spare time and dedicated attention, which is difficult to find! 
I'm pretty happy with the general idea but the details need some work. 
Hopefully I'll make progress on this at ZuriHac next month, but I don't 
want to guarantee anything. If anyone would be willing to help finish 
off the proposal, I'd be happy to chat.

An issue that is not discussed in the proposal, but which we may want to 
reconsider, is that OverloadedRecordUpdate as currently envisaged is 
fork-like: it changes the meaning of record update syntax but both the 
traditional and overloaded forms have advantages. Thus it might be 
sensible to have a distinct syntax for overloaded updates.

I've cleared the merge request milestone as it is no longer realistic to 
get the implementation into 9.4.1.

All the best,

Adam



On 11/05/2022 21:56, John Walker wrote:
> Hello Committee,
> I was wondering if there are any near to middle term plans to move 
> forward with hasField redesign which I believe is an enabler for setter 
> with record dot syntax. The ticket 
> (https://gitlab.haskell.org/ghc/ghc/-/merge_requests/3257 
> <https://gitlab.haskell.org/ghc/ghc/-/merge_requests/3257>) has a 
> milestone of 9.4.1 and it looks like the proposal is done 
> (https://github.com/adamgundry/ghc-proposals/blob/hasfield-redesign/proposals/0000-hasfield-redesign.rst 
> <https://github.com/adamgundry/ghc-proposals/blob/hasfield-redesign/proposals/0000-hasfield-redesign.rst>) 
> pending feedback some time ago but hasn't got to discussions yet 
> (https://github.com/ghc-proposals/ghc-proposals/pull/0 
> <https://github.com/ghc-proposals/ghc-proposals/pull/0>).
> thanks
> John


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Adam Gundry, Haskell Consultant
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