[Haskell-cafe] Lifted Spine View

Andres Löh andres.loeh at googlemail.com
Mon Nov 21 11:15:37 CET 2011

Hi there.

>    I tried to follow the program of the paper "Scrap your boilerpolate"
> Revolutions. Unfortunately,
> I found the program in the section lifted spine view does not compile in my
> GHC, could anybody
>  point out where I am wrong? Many Thanks
> My code is posted here http://hpaste.org/54357

You have to flip the two fields of (:->), i.e., the type has to be
first and the annotated term has to be second. This is because pattern
matching on GADTs and refinement is implicitly left-to-right in GHC.
The paper presents it the other way round and remarks on the flipped
order in a footnote near the beginning.


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