User constructed types with new Data.Typeable and Data.Reflection

Ben Gamari ben at
Tue Feb 13 20:33:26 UTC 2018

Development <dev at> writes:

> Ah thanks. I had no idea the `App` pattern actually was bidirectional. I had tried the `Con’` pattern but that is only valid for deconstruction.
> Is there any way to tell in the docs whether a pattern is bidirectional?
Hmmm, that is a good question. Indeed this appears to be quite unclear.

Alex, is this a known issue?


- Ben

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