Re: Fractional precedences? Re: Operator precedence help

I definitely prefer this approach. I do not like absolutely levels, whether natural numbers or fractional. At the end of the day, that's all order-maintance for a *global* total preorder, and such a design will always result in unforeseeable interactions between independently-developed operators, not to mention increasingly ludicrously-precise fractions. This may sound like low-priority design pedantry, but I suspect (probably because I myself was taught with scheme) that spooky-action-at-a-distance precedence greatly harms beginning programmers, causing confusion or at least delaying the understanding that expressions are arbitrarily deep trees. John On 8/17/20 12:12 PM, Carter Schonwald wrote:

Oh yeah! I feel like everyone’s wondered about that approach. But it definitely would need some experiments to validate. But in some ways it’d be super fascinating.

On Mon, Aug 17, 2020 at 9:40 AM Henning Thielemann mailto:lemming@henning-thielemann.de> wrote:

On Sun, 16 Aug 2020, Carter Schonwald wrote:

> I do think that the work needed to actually support fractional > precedence in ghc is pretty minimal.  Or at least I remember having a > conversation about it a few years ago, and the conclusion was that >  adding precedence would be super easy to do, but just lacked any good > motivating example from real libraries.

I remember this discussion, too, and I guess that it was started by Simon Marlow and it ended with recalling that decades ago something more advanced was discussed: Groups of equal precedence and relations between the groups. But that one was too complicated to be implemented.

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