Special treatment of family and role in the parser

Richard Eisenberg eir at cis.upenn.edu
Thu Jan 21 15:12:30 UTC 2016


My opinion is that if we can avoid stealing syntax, we should. I am indeed concerned about complicating the parser overmuch... but I don't think that parser code complexity should, by itself, drive the language design.

Richard

On Jan 21, 2016, at 9:50 AM, Jan Stolarek <jan.stolarek at p.lodz.pl> wrote:

> I'll take a look at the parser, see if we can do better.
> 
>> I also suggest that keywords introduced by GHC extensions should be lexed as keywords regardless
>> of  whether extension is enabled or not: this way users won't get spurious errors if they
>> suddenly enable extension and it turns out that some of their identifiers have become keywords.
> I would be cautious here. Patch I am working on right now will use "kind" as a reserved 
> identifier. It will only be allowed after `data` keyword. Making it a reserved word everywhere 
> would be a major issue as many people doing type-level programming have variables named "kind". 
> You ar right that problem would be much smaller if the keyword was "datakind" but somehow I am 
> reluctant to seeing things like "datakindmember", "typeinstance", etc. What others think about 
> this proposal?
> 
> Janek
> 
> ---
> Politechnika Łódzka
> Lodz University of Technology
> 
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