Warning: The install command is a part of the legacy v1 style of cabal usage.

Please switch to using either the new project style and the new-install
command or the legacy v1-install alias as new-style projects will become the
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replicate a working v1- use case with the new-style commands.

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Resolving dependencies...
Starting     alist-0.1.0.1
Building     alist-0.1.0.1
Failed to install alist-0.1.0.1
Build log ( /home/builder/.cabal/logs/ghc-8.6.1/alist-0.1.0.1-3KzbYBJmLYQAxrVJDLx6dc.log ):
cabal: Entering directory '/tmp/cabal-tmp-2418/alist-0.1.0.1'
Configuring alist-0.1.0.1...
Preprocessing library for alist-0.1.0.1..
Building library for alist-0.1.0.1..
[1 of 1] Compiling Data.AList       ( Data/AList.hs, dist/build/Data/AList.o )

Data/AList.hs:12:10: error:
    • No instance for (Semigroup (AList a))
        arising from the superclasses of an instance declaration
    • In the instance declaration for ‘Monoid (AList a)’
   |
12 | instance Monoid (AList a) where 
   |          ^^^^^^^^^^^^^^^^
cabal: Leaving directory '/tmp/cabal-tmp-2418/alist-0.1.0.1'
cabal: Error: some packages failed to install:
alist-0.1.0.1-3KzbYBJmLYQAxrVJDLx6dc failed during the building phase. The
exception was:
ExitFailure 1