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 default in the next version of cabal-install. Please file a bug if you cannot replicate a working v1- use case with the new-style commands. For more information, see: https://wiki.haskell.org/Cabal/NewBuild Resolving dependencies... Starting auto-update-0.1.6 Starting base-orphans-0.8.1 Starting colour-2.3.5 Starting base-compat-0.11.0 Building base-orphans-0.8.1 Building auto-update-0.1.6 Building colour-2.3.5 Building base-compat-0.11.0 Completed base-orphans-0.8.1 Starting dlist-0.8.0.7 Building dlist-0.8.0.7 Completed auto-update-0.1.6 Starting easy-file-0.2.2 Building easy-file-0.2.2 Completed dlist-0.8.0.7 Starting githash-0.1.3.3 Completed easy-file-0.2.2 Starting hashable-1.3.0.0 Building githash-0.1.3.3 Building hashable-1.3.0.0 Completed colour-2.3.5 Starting integer-logarithms-1.0.3 Completed githash-0.1.3.3 Starting monad-loops-0.4.3 Building integer-logarithms-1.0.3 Completed base-compat-0.11.0 Starting network-3.1.1.0 Building monad-loops-0.4.3 Completed hashable-1.3.0.0 Starting old-locale-1.0.0.7 Completed integer-logarithms-1.0.3 Starting primitive-0.7.0.0 Building old-locale-1.0.0.7 Building primitive-0.7.0.0 Completed monad-loops-0.4.3 Starting random-1.1 Building random-1.1 Completed old-locale-1.0.0.7 Starting split-0.2.3.3 Building network-3.1.1.0 Building split-0.2.3.3 Completed split-0.2.3.3 Starting stm-chans-3.0.0.4 Completed random-1.1 Starting syb-0.7.1 Building syb-0.7.1 Building stm-chans-3.0.0.4 Completed syb-0.7.1 Starting tagged-0.8.6 Building tagged-0.8.6 Completed stm-chans-3.0.0.4 Starting th-abstraction-0.3.1.0 Building th-abstraction-0.3.1.0 Completed network-3.1.1.0 Starting transformers-compat-0.6.5 Building transformers-compat-0.6.5 Completed tagged-0.8.6 Starting unix-compat-0.5.2 Completed primitive-0.7.0.0 Starting unliftio-core-0.1.2.0 Building unix-compat-0.5.2 Building unliftio-core-0.1.2.0 Completed transformers-compat-0.6.5 Starting zlib-0.6.2.1 Completed unliftio-core-0.1.2.0 Starting time-compat-1.9.2.2 Completed th-abstraction-0.3.1.0 Starting ansi-terminal-0.10.1 Building zlib-0.6.2.1 Completed unix-compat-0.5.2 Starting unordered-containers-0.2.10.0 Building time-compat-1.9.2.2 Building ansi-terminal-0.10.1 Building unordered-containers-0.2.10.0 Completed ansi-terminal-0.10.1 Starting async-2.2.2 Completed time-compat-1.9.2.2 Starting old-time-1.1.0.3 Building async-2.2.2 Completed zlib-0.6.2.1 Starting uuid-types-1.0.3 Building uuid-types-1.0.3 Building old-time-1.1.0.3 Completed async-2.2.2 Starting edit-distance-0.2.2.1 Building edit-distance-0.2.2.1 Completed uuid-types-1.0.3 Starting vector-0.12.0.3 Building vector-0.12.0.3 Completed old-time-1.1.0.3 Starting scientific-0.3.6.2 Completed unordered-containers-0.2.10.0 Starting transformers-base-0.4.5.2 Building scientific-0.3.6.2 Building transformers-base-0.4.5.2 Completed edit-distance-0.2.2.1 Starting exceptions-0.10.3 Building exceptions-0.10.3 Completed transformers-base-0.4.5.2 Starting ansi-wl-pprint-0.6.9 Building ansi-wl-pprint-0.6.9 Completed scientific-0.3.6.2 Starting typed-process-0.2.6.0 Building typed-process-0.2.6.0 Completed exceptions-0.10.3 Starting streaming-commons-0.2.1.1 Completed ansi-wl-pprint-0.6.9 Starting unix-time-0.4.7 Building streaming-commons-0.2.1.1 Building unix-time-0.4.7 Completed typed-process-0.2.6.0 Starting monad-control-1.0.2.3 Building monad-control-1.0.2.3 Completed unix-time-0.4.7 Starting attoparsec-0.13.2.3 Building attoparsec-0.13.2.3 Completed monad-control-1.0.2.3 Starting resourcet-1.2.2 Building resourcet-1.2.2 Completed streaming-commons-0.2.1.1 Starting optparse-applicative-0.15.1.0 Building optparse-applicative-0.15.1.0 Completed resourcet-1.2.2 Starting fast-logger-3.0.0 Building fast-logger-3.0.0 Completed fast-logger-3.0.0 Starting lifted-base-0.2.3.12 Completed attoparsec-0.13.2.3 Building lifted-base-0.2.3.12 Completed optparse-applicative-0.15.1.0 Starting optparse-simple-0.1.1.2 Building optparse-simple-0.1.1.2 Completed lifted-base-0.2.3.12 Completed optparse-simple-0.1.1.2 Completed vector-0.12.0.3 Starting vector-algorithms-0.8.0.1 Starting aeson-1.4.6.0 Building vector-algorithms-0.8.0.1 Building aeson-1.4.6.0 Completed vector-algorithms-0.8.0.1 Starting mono-traversable-1.0.13.0 Building mono-traversable-1.0.13.0 Completed mono-traversable-1.0.13.0 Starting conduit-1.3.1.1 Completed aeson-1.4.6.0 Building conduit-1.3.1.1 Completed conduit-1.3.1.1 Starting conduit-extra-1.3.4 Building conduit-extra-1.3.4 Completed conduit-extra-1.3.4 Starting monad-logger-0.3.30 Building monad-logger-0.3.30 Completed monad-logger-0.3.30 Starting duet-0.0.2 Building duet-0.0.2 Failed to install duet-0.0.2 Build log ( /home/builder/.cabal/logs/ghc-8.6.3/duet-0.0.2-CdkOhG3zYwo9Zo8hOGpS6T.log ): cabal: Entering directory '/tmp/cabal-tmp-17774/duet-0.0.2' Configuring duet-0.0.2... Preprocessing library for duet-0.0.2.. Building library for duet-0.0.2.. [ 1 of 14] Compiling Control.Monad.Supply ( src/Control/Monad/Supply.hs, dist/build/Control/Monad/Supply.o ) src/Control/Monad/Supply.hs:50:25: error: • Could not deduce (Control.Monad.Fail.MonadFail m) arising from a do statement with the failable pattern ‘(x : xs)’ from the context: Monad m bound by the instance declaration at src/Control/Monad/Supply.hs:49:10-47 Possible fix: add (Control.Monad.Fail.MonadFail m) to the context of the instance declaration • In a stmt of a 'do' block: (x : xs) <- get In the second argument of ‘($)’, namely ‘do (x : xs) <- get put xs return x’ In the expression: SupplyT $ do (x : xs) <- get put xs return x | 50 | supply = SupplyT $ do (x:xs) <- get | ^^^^^^^^^^^^^ cabal: Leaving directory '/tmp/cabal-tmp-17774/duet-0.0.2' cabal: Error: some packages failed to install: duet-0.0.2-CdkOhG3zYwo9Zo8hOGpS6T failed during the building phase. The exception was: ExitFailure 1