警告：此处有新的Haskell用户
我正在尝试安装Hoogle的CLI版本以跟随教程。我在Haskell Platform 2013.2.0.0上看到以下内容，适用于Mac OS X，64位。
其他信息：〜/ Library / Haskell / bin在我的路径中。我安装了alex和happy（以及我认为实际定义了BuilderResponse的wai）。这不是原始安装的成绩单（在失败之前安装了大量的东西），但它就是我现在所处的位置。对于咯咯笑，我在Fedora 19（X86_64）上尝试了同样的事情，它也失败了，所以我不认为它是特定于Mac的。
% cabal update
Downloading the latest package list from hackage.haskell.org
% cabal -V
cabal-install version 1.18.0.2
using version 1.18.1.2 of the Cabal library
% cabal install hoogle
Resolving dependencies...
Configuring hoogle-4.2.23...
Building hoogle-4.2.23...
Preprocessing library hoogle-4.2.23...
[ 1 of 46] Compiling Paths_hoogle ( dist/build/autogen/Paths_hoogle.hs, dist/build/Paths_hoogle.o )
[ 2 of 46] Compiling Data.TypeMap ( src/Data/TypeMap.hs, dist/build/Data/TypeMap.o )
[ 3 of 46] Compiling Data.Heap ( src/Data/Heap.hs, dist/build/Data/Heap.o )
[ 4 of 46] Compiling Hoogle.Score.Type ( src/Hoogle/Score/Type.hs, dist/build/Hoogle/Score/Type.o )
[ 5 of 46] Compiling Hoogle.Score.Scoring ( src/Hoogle/Score/Scoring.hs, dist/build/Hoogle/Score/Scoring.o )
[ 6 of 46] Compiling Hoogle.Score.All ( src/Hoogle/Score/All.hs, dist/build/Hoogle/Score/All.o )
[ 7 of 46] Compiling General.Base ( src/General/Base.hs, dist/build/General/Base.o )
[ 8 of 46] Compiling General.System ( src/General/System.hs, dist/build/General/System.o )
[ 9 of 46] Compiling Hoogle.Type.Language ( src/Hoogle/Type/Language.hs, dist/build/Hoogle/Type/Language.o )
[10 of 46] Compiling General.Util ( src/General/Util.hs, dist/build/General/Util.o )
[11 of 46] Compiling General.Web ( src/General/Web.hs, dist/build/General/Web.o )
src/General/Web.hs:44:19:
Not in scope: data constructor `ResponseBuilder'
Failed to install hoogle-4.2.23
cabal: Error: some packages failed to install:
hoogle-4.2.23 failed during the building phase. The exception was:
ExitFailure 1
答案 0 :(得分：5)
看起来Neil尚未更新hoogle以使用最新的wai包。短期解决方案是强制cabal选择旧版本的违规套餐（wai）：
cabal install hoogle --constraint='wai<2.0'
编辑：注意wai 2.0仅在4天前发布，hackage没有主动告知开发人员有关破损的信息，所以这并不奇怪。