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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Resolving dependencies...
Starting     dobutok-0.1.0.0
Building     dobutok-0.1.0.0
Failed to install dobutok-0.1.0.0
Build log ( /home/builder/.cabal/logs/ghc-8.6.3/dobutok-0.1.0.0-7UwjRbfo9FKAQvLStC935W.log ):
cabal: Entering directory '/tmp/cabal-tmp-8917/dobutok-0.1.0.0'
Configuring dobutok-0.1.0.0...
Preprocessing library for dobutok-0.1.0.0..
Building library for dobutok-0.1.0.0..

System/Extended/MathPauses/PrintMessage.hs:13:8: error:
    File name does not match module name:
    Saw: ‘System.Extended.MathPauses’
    Expected: ‘System.Extended.MathPauses.PrintMessage’
   |
13 | module System.Extended.MathPauses (
   |        ^^^^^^^^^^^^^^^^^^^^^^^^^^
cabal: Leaving directory '/tmp/cabal-tmp-8917/dobutok-0.1.0.0'
cabal: Error: some packages failed to install:
dobutok-0.1.0.0-7UwjRbfo9FKAQvLStC935W failed during the building phase. The
exception was:
ExitFailure 1