QuasiQuotation library for programmatic generation of Javascript code. (http://www.haskell.org/haskellwiki/Jmacro)

#4jmacro-0.6.14 build failure with GHC 8.4

Add semigroup instances See also: https://ghc.haskell.org/trac/ghc/wiki/Migration/8.4#SemigroupMonoidsuperclasses

[3 of 8] Compiling Language.Javascript.JMacro.Base ( Language/Javascript/JMacro/Base.hs, .stack-work/dist/x86_64-osx/Cabal-2.2.0.1/build/Language/Javascript/JMacro/Base.o )

/Users/dan/scratch/jmacro-0.6.14/Language/Javascript/JMacro/Base.hs:137:10: error:
    • No instance for (Semigroup JStat)
        arising from the superclasses of an instance declaration
    • In the instance declaration for ‘Monoid JStat’
    |
137 | instance Monoid JStat where
    |          ^^^^^^^^^^^^

I was able to reproduce this locally like so:

stack unpack jmacro-0.6.14 && cd jmacro-0.6.14
edit stack.yaml # add the following stack.yaml
stack build --test --bench --no-run-benchmarks
# stack.yaml
resolver: nightly-2018-05-10
extra-deps:
- wl-pprint-text-1.1.1.1
- base-compat-0.10.1
- aeson-1.3.1.0