[Haskell-cafe] tuple and pattern synonym

Kazu Yamamoto (=?iso-2022-jp?B?GyRCOzNLXE9CSScbKEI=?=) kazu at iij.ad.jp
Mon May 18 06:29:34 UTC 2020

Hi David,

> You need to use a view pattern with an explicitly bidirectional pattern
> synonym:
> pattern P :: (Int,Int) -> Foo
> pattern P xy <- ((\(Foo x y) -> (x, y)) -> xy)
>   where
>     P (x, y) = Foo x y


To maintain backward compatibility of the "network" library, I have
created a PR:


Thank you for your suggestion!


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