我試圖安裝最新版本的海斯特,但是errors-1.3.1
這是一個依賴項無法安裝。有關如何克服這個問題的任何建議?cabal安裝錯誤-1.3.1失敗
$ cabal install errors-1.3.1
Resolving dependencies...
Configuring errors-1.3.1...
Building errors-1.3.1...
Preprocessing library errors-1.3.1...
[1 of 5] Compiling Data.EitherR (Data/EitherR.hs, dist/build/Data/EitherR.o)
[2 of 5] Compiling Control.Error.Util (Control/Error/Util.hs, dist/build/Control/Error/Util.o)
Control/Error/Util.hs:74:10:
Could not deduce (Monad m) arising from a use of `fmap'
from the context (Functor m)
bound by the type signature for
fmapRT :: Functor m => (a -> b) -> EitherT l m a -> EitherT l m b
at Control/Error/Util.hs:74:1-13
Possible fix:
add (Monad m) to the context of
the type signature for
fmapRT :: Functor m => (a -> b) -> EitherT l m a -> EitherT l m b
In the expression: fmap
In an equation for `fmapRT': fmapRT = fmap
cabal: Error: some packages failed to install:
errors-1.3.1 failed during the building phase. The exception was:
ExitFailure 1
版本1.3.1是舊的,也許你應該'cabal update'並嘗試安裝1.4.1。如果這是一個由cabal選擇的dep,那麼使用--constraint'errors == 1.4.1' – 2013-02-09 23:51:59
爲什麼最新的Heist(0.11.0)依賴於錯誤-1.3。*? – dan 2013-02-10 00:23:57
Heist的git回購實際上糾正了這個問題。感謝您的幫助。 – dan 2013-02-10 00:25:22