hlint

When I try to install hlint I get errors surrounding old-time-1.1.0.3

北战南征 提交于 2019-12-09 17:35:23
问题 I first tried to install Hlint. cabal install hlint but then I got the error: cabal: Error: some packages failed to install: cpphs-1.20.2 depends on old-time-1.1.0.3 which failed to install. haskell-src-exts-1.18.2 depends on old-time-1.1.0.3 which failed to install. hlint-1.9.37 depends on old-time-1.1.0.3 which failed to install. old-time-1.1.0.3 failed during the configure step. The exception was: ExitFailure 77 Then I tried to install ghc-mod since I read that hlint is a dependency of

When I try to install hlint I get errors surrounding old-time-1.1.0.3

百般思念 提交于 2019-12-04 04:03:47
I first tried to install Hlint. cabal install hlint but then I got the error: cabal: Error: some packages failed to install: cpphs-1.20.2 depends on old-time-1.1.0.3 which failed to install. haskell-src-exts-1.18.2 depends on old-time-1.1.0.3 which failed to install. hlint-1.9.37 depends on old-time-1.1.0.3 which failed to install. old-time-1.1.0.3 failed during the configure step. The exception was: ExitFailure 77 Then I tried to install ghc-mod since I read that hlint is a dependency of that package(?). Thinking that it might resolve the problem. So i did cabal install ghc-mod which gave me

stack install ghc-mod fails with dependencies conflicts on OSX 10.13.4

时间秒杀一切 提交于 2019-12-01 04:49:48
When I try to install ghc-mod via stack I end up having these depencies conflicts Error: While constructing the build plan, the following exceptions were encountered: In the dependencies for ghc-mod-5.8.0.0: Cabal-2.0.1.1 from stack configuration does not match >=1.18 && <1.25 (latest matching version is 1.24.2.0) base-4.10.1.0 from stack configuration does not match >=4.6.0.1 && <4.10 (latest matching version is 4.9.1.0) cabal-helper must match <0.8 && >=0.7.3.0, but the stack configuration has no specified version (latest matching version is 0.7.3.0) extra-1.6.8 from stack configuration does

stack install ghc-mod fails with dependencies conflicts on OSX 10.13.4

感情迁移 提交于 2019-12-01 02:05:02
问题 When I try to install ghc-mod via stack I end up having these depencies conflicts Error: While constructing the build plan, the following exceptions were encountered: In the dependencies for ghc-mod-5.8.0.0: Cabal-2.0.1.1 from stack configuration does not match >=1.18 && <1.25 (latest matching version is 1.24.2.0) base-4.10.1.0 from stack configuration does not match >=4.6.0.1 && <4.10 (latest matching version is 4.9.1.0) cabal-helper must match <0.8 && >=0.7.3.0, but the stack configuration

What does eta reduce mean in the context of HLint

巧了我就是萌 提交于 2019-11-27 03:21:09
问题 I'm looking at the tutorial http://haskell.org/haskellwiki/How_to_write_a_Haskell_program import System.Environment main :: IO () main = getArgs >>= print . haqify . head haqify s = "Haq! " ++ s When running this program under HLint it gives the following error; ./Haq.hs:11:1: Warning: Eta reduce Found: haqify s = "Haq! " ++ s Why not: haqify = ("Haq! " ++ ) Can someone shed some light on what exactly "Eta Reduce" means in this context? 回答1: Eta reduction is turning \x -> f x into f as long