Really portable installation of Haskell on Windows

Question

Is it possible to have a truly portable Haskell installation on Windows, so everything related to Haskell happens in the same directory. I want to have Haskell installed on a USB drive, so I can use it on any other Windows computer just by plugging it in.

This means that when I say cabal install somePackageeverything happens locally and relative to this single directory (nb for different computers may have a different drive letter assigned to the USB drive). I would like to be able to run this cabal install somePackageon any Windows machine. It would also be nice if I could copy the contents of the USB drive to a local hard drive, and it still works from there (on some Windows computers, USB drives are read-only).

I am aware of the following related StackOverflow questions here and here . Can I customize the cabal configuration file to use relative paths? What about other Haskell tools (e.g. winghci)?

So how do I do this? Install the Haskell platform portable, and then do what?

Answer 1

Follow the procedure below:

• Use a portable installation to install the Haskell Platform , for example. h:\dev\hp. Select Do Not Create Shortcuts. To install Haskell Stack, select h:\dev\hp\local\binas the destination folder. De select Add to user% PATH%.

• You should get the following first level directory structure:

  dev
    hp
      8.0.1
      local
        bin (this where stack.exe gets installed)
  

• Create additional subfolders:

  mkdir projects
  mkdir user
  cd user
  mkdir AppData
  mkdir AppData\Roaming
  
  dev
    hp
      projects
      user
        AppData
          Roaming
  

• junction user. user\create-symlink.bat . .

  %~dp0junction -nobanner -accepteula -d "%~dp0Application Data"
  %~dp0junction -nobanner -accepteula "%~dp0Application Data" %~dp0AppData\Roaming
  junction "Application Data" AppData\Roaming
  

• haskell.bat h:\dev\hp :

  @ECHO OFF
  set HSROOT=%~dp08.0.1
  SET USERPROFILE=%~dp0user
  SET Path=%HSROOT%\bin;%HSROOT%\winghci;%~dp0local\bin;%HSROOT%\mingw\bin;%HSROOT%\msys\usr\bin;%HSROOT%\lib;%HSROOT%\lib\extralibs\bin;%Path%
  CMD /k "cd %~dp0projects"
  

• haskell.bat . user\AppData\Roaming

  cabal update
  cabal user-config init
  stack setup
  

• cabal (user\AppData\Roaming\cabal\config) , :

  remote-repo-cache: $prefix\..\..\user\AppData\Roaming\cabal\packages
  world-file: $prefix\..\..\user\AppData\Roaming\cabal\world
  extra-prog-path: $prefix\..\msys\usr\bin
  extra-lib-dirs: $prefix\..\mingw\lib
  extra-include-dirs: $prefix\..\mingw\include
  build-summary: $prefix\..\..\user\AppData\Roaming\cabal\logs\build.log
  

• , : user\AppData\Roaming\ghc\i386-mingw32-8.0.1\package.conf.d\*.conf

  • $topdir ( 8.0.1, , h:\dev\hp\8.0.1\lib). , , h:\\dev\\hp\user\\Application Data $topdir\\..\\..\\user\\AppData\\Roaming. , h:\dev\hp\8.0.1, $topdir\...

• , . user\AppData\Roaming\stack\snapshots\XXX\pkgdb:

• - :

  `ghc-pkg recache --global`
  `ghc-pkg recache --user`
  `ghc-pkg recache --package-db="h:\dev\hp\user\AppData\Roaming\stack\snapshots\XXX\pkgdb"`
  

• , . cabal install --enable-relocatable <package> , .

• , , . haskell.bat , ghc, cabal, stack, winghci ..

• . , gcc, :

  Configuring network-2.6.3.1...
  bash.exe: warning: could not find /tmp, please create!
  configure: WARNING: unrecognized options: --with-compiler
  checking build system type... bash.exe: warning: could not find /tmp, please create!
  bash.exe: warning: could not find /tmp, please create!
  i686-pc-mingw32
  checking host system type... i686-pc-mingw32
  checking for gcc... h:\dev\hp\80227D~1.1Ăé´ÉŐĂőýŽÇ┬ćýŁŻ┬îŃąÇĂéňżö┬łŃŽ«ĂéŃąÇĂéň庤ťO
  checking whether the C compiler works... no
  configure: error: in `/cygdrive/c/DOCUME~1/UserName/LOCALS~1/Temp/stack4268/network-2.6.3.1':
  configure: error: C compiler cannot create executables
  See `config.log' for more details
  

  , configure script gcc (h:\dev\hp\80227D~1.1Ăé´ÉŐĂőýŽÇ┬ćýŁŻ┬îŃąÇĂéňżö┬łŃŽ«ĂéŃąÇĂéň庤ťO). , , , :

  stack unpack network-2.6.3.1
  cd network-2.6.3.1
  stack init
  # edit `configure` script and put `CC=` on the first line to kill system supplied path to `gcc`
  stack build
  

Answer 2

:

penultimo :: [Int] -> Int
penultimo l = head(tail(reverse l))