Cabal installing quickcheck version problem
我正在尝试在Ubuntu 10.04上通过cabal安装quickcheck 2。无论我尝试做什么,我总是会遇到以下问题:
1 2 3 4 5 6 7 | $ cabal list quickcheck * QuickCheck Synopsis: Automatic testing of Haskell programs Latest version available: 2.1.1.1 Latest version installed: 1.2.0.0 Homepage: http://www.cse.chalmers.se/~koen License: BSD3 |
这是在干净的Ubuntu 10.04上,仅安装了ghc6和cabal-install apt软件包。在尝试安装quickcheck之前,我已经通过cabal安装了二进制软件包。
它告诉我2.1.1.1可用,但只能安装1.2.0.0。为什么我无法真正安装最新版本?
1 2 3 4 | $ cabal install --dry-run quickcheck Resolving dependencies... In order, the following would be installed (use -v for more details): QuickCheck-1.2.0.0 |
我不确定为什么选择旧版本,但是您可以这样做:
1 2 3 4 5 | $ cabal install --dry-run quickcheck-2.1 Resolving dependencies... In order, the following would be installed (use -v for more details): mtl-1.1.0.2 QuickCheck-2.1 |
您可以在版本号中更具体,但不必。