User constructed types with new Data.Typeable and Data.Reflection
dev at justus.science
Sat Feb 10 10:16:35 UTC 2018
Hey guys I have a (hopefully quick) question.
With the new `Data.Typeable` and `Data.Reflection` in base 4.10 have we really lost the ability for users to compose `TypeRep`’s?
I was using `Data.Typeable` before (mainly `mkTyConApp`). But in the new base 4.10 I cannot find any way to achieve the same goal.
I have read the wiki page Typeable and Typeable/BenGamari and neither explicitly mentions the removal of `mkTyConApp` and similar facilities. In fact the latter mentions potential implementations for user constructed type applications twice with `mkTrApp` at the beginning of the page and `mkApp` at the end.
Furthermore the documentation for `Typeable` (and `Reflection`) also never mentions the fact that this functionality was removed.
My question is this: Is this intentional? Is there now a consensus that there should not be user constructed types? Or is there some subtile issue that I’m missing wich prevents user constructed types for now or always?
Thanks in advance guys.
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