Currently, haskell-src-exts-util-0.2.1.2 fails to build on GHC 8.4.1 since Semigroup has become a superclass of Monoid, and Vars lacks a Semigroup instance. This fixes the issue.
I opted to avoid some CPP by depending on the semigroups package to provide the Semigroup class on GHC 7.10 and earlier (before Semigroup was added to base). If you'd prefer to avoid incurring an extra dependency, I could alternatively remove the semigroups dependency and only define the Semigroup instances on base-4.9 or later (at the cost of some CPP).
pepeiborra
commented
6 years ago
Currently,
haskell-src-exts-util-0.2.1.2fails to build on GHC 8.4.1 sinceSemigrouphas become a superclass ofMonoid, andVarslacks aSemigroupinstance. This fixes the issue.I opted to avoid some CPP by depending on the
semigroupspackage to provide theSemigroupclass on GHC 7.10 and earlier (beforeSemigroupwas added tobase). If you'd prefer to avoid incurring an extra dependency, I could alternatively remove thesemigroupsdependency and only define theSemigroupinstances onbase-4.9or later (at the cost of some CPP).