Parsing funny arrows
kiss.csongor.kiss at gmail.com
Sat Aug 29 07:16:46 UTC 2020
Thanks a lot Vlad and Shayne, that indeed did the trick!
Out of curiosity, how could I have figured out that this was the culprit? The parse
error I got was a bit puzzling, and I couldn't find any flags that would give more information
(I think I was looking for the parser equivalent of -ddump-tc-trace).
> On 29 Aug 2020, at 00:51, Shayne Fletcher <shayne.fletcher.50 at gmail.com> wrote:
> On Fri, Aug 28, 2020 at 7:48 PM Shayne Fletcher <shayne.fletcher.50 at gmail.com <mailto:shayne.fletcher.50 at gmail.com>> wrote:
> On Fri, Aug 28, 2020 at 7:38 PM Vladislav Zavialov <vladislav at serokell.io <mailto:vladislav at serokell.io>> wrote:
> Hi Csongor,
> I believe the reason for this failure is that a -> @m b gets parsed as a -> @(m b).
> Why is that? Because a ‘btype’ includes type-level application.
> If you replace the ‘btype’ after PREFIX_AT with an ‘atype’, this particular issue should go away. At least that’s my hypothesis, I haven’t tested it.
> I confirm that this is correct and with that change the example string reduces as hoped.
> - Vlad
> Also, with that correction there are no new shift/reduce conflicts. The original rule gave rise to 3.
> Shayne Fletcher
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