What Haskell users are actively maintaining or deving software using ghc <8

[Joseph C. Sible]

On Wed, May 27, 2020 at 5:27 PM Henning Thielemann
<lemming at henning-thielemann.de> wrote:
>
> I am not giving up anything, because I test my code against both 7.4.2 AND
> newer GHC versions.

You're giving up the ability to use every new feature introduced since
then, since using them would mean your code stops working under 7.4.2.

> What linter can easily catch "instance Foldable ((,) a)"?

HLint can: for example, if you run hlint on a file containing "foo =
maximum (4,2)", it says "Warning: Using maximum on tuple"

Joseph C. Sible