官方公告 Managing Haskell packages with GHC 7.8.2

裡面寫了

Moving every package that is not ghc or cabal-install to [community]. This will allow better support of the core common haskell libraries since I do not actually use these packages due to cabal-install.

其實我根本看不懂該怎麼做= ="
反正我一定不是唯一一個看不懂的(?)
所以就查到了這篇 [SOLVED] Problems upgrading some haskell packages
遇到的情形似乎跟我一樣
下了 sudo pacman -Syu 後噴了

:: haskell-transformers: requires ghc=7.6.3-1  

然後 pacman -Qs ghc 後也一樣已經安裝了
然後底下有人提供了解法

sudo pacman -Rcs haskell-transformers  

把跟 haskell-transformers 有關的套件都移除掉以後
再重新下一次 sudo pacman -Syu 就可以了

底下的回覆有人的解釋是

haskell-transformers was recently removed from extra.
It depends on a specific version of ghc.
There is a newer version of ghc in the repos.
Since haskell-transformers was removed there's no upgrade path to resolve the issue.
You'll have to do it manually.
Edit: Removed from the repos entirely.
Not moved from extra to community like the other haskell packages.

恩 應該就是這樣吧