I never set the prefix manually and just use the default. The default for Windows is $APPDATA/Cabal. Where that ends up depends on your version of Windows. On Windows "--user" is also the default. On Thu, Jun 16, 2011 at 10:47 AM, Dmitri O.Kondratiev wrote:

On Thu, Jun 16, 2011 at 6:18 PM, Ryan Yates wrote:

...

There is a nice table in the cabal docs that explains how prefix gets used:

http://www.haskell.org/ghc/docs/7.0.4/html/Cabal/builders.html#simple-paths

For Vista and above C:\Documents and settings\myusername\ is C:\Users\myusername.  The equivalent to $HOME on Windows would be $USERPROFILE but the syntax of expanding an environment variable is going to depend on the shell you are using:

cmd window:  cabal install --prefix=%USERPROFILE% --user PowerShell:  cabal install --prefix=${env:USERPROFILE} --user msys window:  cabal install --prefix=$USERPROFILE --user

Note that msys does define $HOME and it is a different physical path than $USERPROFILE.

Ryan, thanks! This win32 $HOME story is clear now. And why not just use: "cabal install" instead of: "cabal install --prefix=%USERPROFILE% --user" for win32 platform? Where in this case "cabal install" root will be?