A question about roles.

[Alexander Eyers-Taylor]

Hello

I have reread the comment about TyConAppCo and I now understand how it 
works and this is all how it should work. I was just slightly confused 
to start with. The coercion was representational but the arguments were 
nominal.

Thanks

Alex

On 16/08/15 13:34, Richard Eisenberg wrote:
> Hi Alex,
>
> Do you have a concrete example? With the -dcore-lint flag, the Core is checked, including all the roles.
>
> Thanks,
> Richard
>
> On Aug 16, 2015, at 7:47 AM, Alexander Eyers-Taylor <aeyerstaylor11 at gmail.com> wrote:
>
>> Hello
>>
>> I have noticed in looking at some core that GADT type constructors are often applied with a representational role. These constructors are explicitly marked as nominal.
>>
>> Is this information just ignored at a Core level or is this invalid core?
>>
>> Looking at the code a see that we if we downgrade a TyConAppCo we unconditionally change it to a representational role after changing its children. I think this is where it is introduced.
>>
>> Alex ET
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