Parsing funny arrows

Shayne Fletcher shayne.fletcher.50 at
Fri Aug 28 23:48:32 UTC 2020

On Fri, Aug 28, 2020 at 7:38 PM Vladislav Zavialov <vladislav at>

> 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

Shayne Fletcher
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