cabalを入れ直すときに

cabalは依存関係ソルバが賢くないのでcabal installを使うと死ぬ．

これからはsandboxを使いたい． その為には，現状の環境を綺麗にしたい．

rm -r $HOME/.cabalのみの場合では， cabal install cabal-installをした時に画像のようなる．

$ ./cabal install cabal-install
Resolving dependencies...
Configuring cabal-install-1.20.0.3...
Failed to install cabal-install-1.20.0.3
Build log ( /Users/mocchi/.cabal/logs/cabal-install-1.20.0.3.log ):
cabal: Error: some packages failed to install:
cabal-install-1.20.0.3 failed during the configure step. The exception was:
user error (
/var/folders/vl/chr7_09s77sdhxgbhm3zr3q00000gn/T/cabal-install-1.20.0.3-33440/cabal-install-1.20.0.3/dist/setup/setup.hs:1:8:
Could not find module ‘Distribution.Simple’
There are files missing in the ‘Cabal-1.20.0.2’ package,
try running 'ghc-pkg check'.
Use -v to see a list of the files searched for.
)

option:enable style:terminal

解決方法

$ rm -r $HOME/.(cabal|ghc)

option:enable style:terminal

これで，cabal install cabal-installをやり直せる