我在Windows上安装了Haskell平台。我正在尝试从现有的cabal沙箱构建现有项目。每当我尝试重新安装时，所有软件包都会失败并显示以下错误：
cabal.exe: expected an absolute directory name for --prefix:
想知道我需要指定一个绝对的指示牌。 Cabal安装在这里：
注意：我正在使用Powershell来执行这些命令。
C:\Users\user\AppData\Roaming\cabal\bin\cabal.exe
这里是完整的输出。
websockets-snap-0.8.2.1 (new package)
Project-0.1 (new package)
cabal.exe: The following packages are likely to be broken by the reinstalls:
haskell-platform-2013.2.0.0
cgi-3001.1.7.5
Use --force-reinstalls if you want to install anyway.
PS C:\Users\user\Project> cabal install --force-reinstalls
Resolving dependencies...
Warning: The following packages are likely to be broken by the reinstalls:
haskell-platform-2013.2.0.0
cgi-3001.1.7.5
Continuing even though the plan contains dangerous reinstalls.
Configuring Crypto-4.2.5.1...
cabal.exe: expected an absolute directory name for --prefix:
/Users/user/Project/.cabal-sandbox
Failed to install Crypto-4.2.5.1
Configuring MonadRandom-0.1.13...
cabal.exe: expected an absolute directory name for --prefix:
/Users/user/Project/.cabal-sandbox
Failed to install MonadRandom-0.1.13
Configuring SHA-1.6.1...
cabal.exe: expected an absolute directory name for --prefix:
/Users/user/Project/.cabal-sandbox
Failed to install SHA-1.6.1
如何为前缀？
指定绝对目录名称