Resolving dependencies... Configuring base-orphans-0.7... Configuring peano-0.1.0.1... Building peano-0.1.0.1... Building base-orphans-0.7... Installed peano-0.1.0.1 Configuring reflection-2.1.3... Installed base-orphans-0.7 Configuring transformers-0.5.5.0... Building reflection-2.1.3... Building transformers-0.5.5.0... Installed reflection-2.1.3 Installed transformers-0.5.5.0 Configuring mtl-2.2.2... Configuring transformers-compat-0.6.1.6... Building mtl-2.2.2... Building transformers-compat-0.6.1.6... Installed transformers-compat-0.6.1.6 Configuring transformers-base-0.4.5.2... Installed mtl-2.2.2 Configuring mmorph-1.1.2... Building transformers-base-0.4.5.2... Building mmorph-1.1.2... Installed transformers-base-0.4.5.2 Configuring monad-control-1.0.2.3... Building monad-control-1.0.2.3... Installed mmorph-1.1.2 Installed monad-control-1.0.2.3 Configuring monad-classes-0.3.2.1... Building monad-classes-0.3.2.1... Failed to install monad-classes-0.3.2.1 Build log ( /home/builder/.cabal/logs/ghc-8.2.2/monad-classes-0.3.2.1-BY0E9iywP8W1MRhITvfBpQ.log ): cabal: Entering directory '/tmp/cabal-tmp-7437/monad-classes-0.3.2.1' Configuring monad-classes-0.3.2.1... Preprocessing library for monad-classes-0.3.2.1.. Building library for monad-classes-0.3.2.1.. [ 1 of 12] Compiling Control.Monad.Classes.Core ( Control/Monad/Classes/Core.hs, dist/build/Control/Monad/Classes/Core.o ) [ 2 of 12] Compiling Control.Monad.Classes.Effects ( Control/Monad/Classes/Effects.hs, dist/build/Control/Monad/Classes/Effects.o ) [ 3 of 12] Compiling Control.Monad.Classes.Except ( Control/Monad/Classes/Except.hs, dist/build/Control/Monad/Classes/Except.o ) [ 4 of 12] Compiling Control.Monad.Classes.Exec ( Control/Monad/Classes/Exec.hs, dist/build/Control/Monad/Classes/Exec.o ) [ 5 of 12] Compiling Control.Monad.Classes.Proxied ( Control/Monad/Classes/Proxied.hs, dist/build/Control/Monad/Classes/Proxied.o ) [ 6 of 12] Compiling Control.Monad.Classes.Reader ( Control/Monad/Classes/Reader.hs, dist/build/Control/Monad/Classes/Reader.o ) [ 7 of 12] Compiling Control.Monad.Classes.State ( Control/Monad/Classes/State.hs, dist/build/Control/Monad/Classes/State.o ) [ 8 of 12] Compiling Control.Monad.Classes.ReadState ( Control/Monad/Classes/ReadState.hs, dist/build/Control/Monad/Classes/ReadState.o ) [ 9 of 12] Compiling Control.Monad.Classes.Writer ( Control/Monad/Classes/Writer.hs, dist/build/Control/Monad/Classes/Writer.o ) Control/Monad/Classes/Writer.hs:36:26: error: • Variable not in scope: (<>) :: w -> w -> w • Perhaps you meant one of these: ‘<$>’ (imported from Control.Applicative), ‘*>’ (imported from Control.Applicative), ‘<$’ (imported from Control.Applicative) | 36 | tellN _ w = SL.modify (<> w) | ^^ Control/Monad/Classes/Writer.hs:39:24: error: • Variable not in scope: (<>) :: w -> w -> w • Perhaps you meant one of these: ‘<$>’ (imported from Control.Applicative), ‘*>’ (imported from Control.Applicative), ‘<$’ (imported from Control.Applicative) | 39 | tellN _ w = modify' (<> w) | ^^ cabal: Leaving directory '/tmp/cabal-tmp-7437/monad-classes-0.3.2.1' cabal: Error: some packages failed to install: monad-classes-0.3.2.1-BY0E9iywP8W1MRhITvfBpQ failed during the building phase. The exception was: ExitFailure 1