doesn't compile

[danoctavian]

cabal install fails with the following (cabal 1.24):

[ 1 of 15] Compiling Data.Maybe.Util  ( src/Data/Maybe/Util.hs, dist/build/dash-haskell/dash-haskell-tmp/Data/Maybe/Util.o )
[ 2 of 15] Compiling Db               ( src/Db.hs, dist/build/dash-haskell/dash-haskell-tmp/Db.o )
[ 3 of 15] Compiling Options.Db       ( src/Options/Db.hs, dist/build/dash-haskell/dash-haskell-tmp/Options/Db.o )
[ 4 of 15] Compiling FilePath         ( src/FilePath.hs, dist/build/dash-haskell/dash-haskell-tmp/FilePath.o )
[ 5 of 15] Compiling Data.String.Util ( src/Data/String/Util.hs, dist/build/dash-haskell/dash-haskell-tmp/Data/String/Util.o )
[ 6 of 15] Compiling PackageConf      ( src/PackageConf.hs, dist/build/dash-haskell/dash-haskell-tmp/PackageConf.o )
[ 7 of 15] Compiling Options.Documentation ( src/Options/Documentation.hs, dist/build/dash-haskell/dash-haskell-tmp/Options/Documentation.o )
[ 8 of 15] Compiling Control.Monad.M  ( src/Control/Monad/M.hs, dist/build/dash-haskell/dash-haskell-tmp/Control/Monad/M.o )
[ 9 of 15] Compiling Options.Cabal    ( src/Options/Cabal.hs, dist/build/dash-haskell/dash-haskell-tmp/Options/Cabal.o )
[10 of 15] Compiling Haddock.Artifact ( src/Haddock/Artifact.hs, dist/build/dash-haskell/dash-haskell-tmp/Haddock/Artifact.o )
[11 of 15] Compiling Haddock.Sqlite   ( src/Haddock/Sqlite.hs, dist/build/dash-haskell/dash-haskell-tmp/Haddock/Sqlite.o )
[12 of 15] Compiling Pipe.FileSystem  ( src/Pipe/FileSystem.hs, dist/build/dash-haskell/dash-haskell-tmp/Pipe/FileSystem.o )
[13 of 15] Compiling Options          ( src/Options.hs, dist/build/dash-haskell/dash-haskell-tmp/Options.o )
[14 of 15] Compiling Pipe.Conf        ( src/Pipe/Conf.hs, dist/build/dash-haskell/dash-haskell-tmp/Pipe/Conf.o )
[15 of 15] Compiling Main             ( src/Main.hs, dist/build/dash-haskell/dash-haskell-tmp/Main.o )

src/Main.hs:49:6:
    Not in scope: ‘<>’
    Perhaps you meant one of these:
      ‘<$>’ (imported from Options.Applicative),
      ‘*>’ (imported from Options.Applicative),
      ‘<$’ (imported from Options.Applicative)

src/Main.hs:50:6:
    Not in scope: ‘<>’
    Perhaps you meant one of these:
      ‘<$>’ (imported from Options.Applicative),
      ‘*>’ (imported from Options.Applicative),
      ‘<$’ (imported from Options.Applicative)
cabal: Leaving directory '.'
cabal: Error: some packages failed to install:
dash-haskell-1.1.0.2 failed during the building phase. The exception was:
ExitFailure 1
~/Downloads/cabal install  108.09s user 8.79s system 173% cpu 1:07.27 total

[lancelet]

I can get dash-haskell to compile with stack by doing:

# first checkout dash-haskell from GitHub; cd into directory; then...
stack init
# ... stack futzed around for a while but settled on lts-6.27 for dependencies
# now build the project:
stack build
# to install to ~/.local/bin:
stack install

I'm not sure of the cause of your particular error, but <> is very likely from Data.Monoid. You could try adding:

import Data.Monoid ((<>))

to the imports of src/Main.hs (but I think you may have more success with stack).