Haskell如何解决此错误:不支持的扩展名:MultiWayIf
在尝试安装Haskell如何解决此错误:不支持的扩展名:MultiWayIf,haskell,cabal,Haskell,Cabal,在尝试安装friday软件包时,我遇到了错误 Preprocessing library friday-0.2.2.0... src/Vision/Detector/Edge.hs:3:14: Unsupported extension: MultiWayIf cabal: Error: some packages failed to install: friday-0.2.2.0 failed during the building phase. The exception was: Exi
friday
软件包时,我遇到了错误
Preprocessing library friday-0.2.2.0...
src/Vision/Detector/Edge.hs:3:14: Unsupported extension: MultiWayIf
cabal: Error: some packages failed to install:
friday-0.2.2.0 failed during the building phase. The exception was:
ExitFailure 1
如何解决此错误
我正在使用ghc版本7.4.1和
cabal-install version 0.14.0
using version 1.14.0 of the Cabal library
GHC的7.6分支引入了MultiWayIf。您必须升级编译器或修补库。基于,
MultiWayIf
扩展是在7.6.1中添加的。因此,它在ghc 7.4上不起作用。