A question about roles.

Alexander Eyers-Taylor aeyerstaylor11 at gmail.com
Sun Aug 16 11:47:02 UTC 2015


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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