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Resolving dependencies...
Downloading  tyfam-witnesses-0.1.1.2
Downloaded   tyfam-witnesses-0.1.1.2
Starting     tyfam-witnesses-0.1.1.2
Building     tyfam-witnesses-0.1.1.2
Failed to install tyfam-witnesses-0.1.1.2
Build log ( /home/builder/.cabal/logs/ghc-8.6.1/tyfam-witnesses-0.1.1.2-CN0TnUHn3ad8zCnmyLgNjd.log ):
cabal: Entering directory '/tmp/cabal-tmp-13732/tyfam-witnesses-0.1.1.2'
Configuring tyfam-witnesses-0.1.1.2...
Preprocessing library for tyfam-witnesses-0.1.1.2..
Building library for tyfam-witnesses-0.1.1.2..
[1 of 2] Compiling TyFamWitnesses   ( TyFamWitnesses.hs, dist/build/TyFamWitnesses.o )
[2 of 2] Compiling Main             ( Main.hs, dist/build/Main.o )

Main.hs:63:1: error:
    • Expected a type, but
      ‘Elim a_acF4 (c_acF5 -> b_acF6) ~ c_acF5’ has kind
      ‘Constraint’
    • In the definition of data constructor ‘Elim1’
      In the data declaration for ‘ElimRefl’
   |
63 | witnesses [d| type family Elim a b where Elim a (a -> b) = b; Elim a (c -> b) = c -> Elim a b |]
   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
cabal: Leaving directory '/tmp/cabal-tmp-13732/tyfam-witnesses-0.1.1.2'
cabal: Error: some packages failed to install:
tyfam-witnesses-0.1.1.2-CN0TnUHn3ad8zCnmyLgNjd failed during the building
phase. The exception was:
ExitFailure 1