再次在'Hat`上退出失败1

Question

在this question中，我们安装了Hat的依赖项。现在当我尝试做

cabal install Hat

我到最后：

[ 6 of 11] Compiling Environment      ( trans/Environment.hs, dist/build/hat-trans/hat-trans-tmp/Environment.o )

trans/Environment.hs:497:13:
    Not in scope: data constructor `PExplTypeArg'
Failed to install hat-2.8.0.0
World file is already up to date.
cabal: Error: some packages failed to install:
hat-2.8.0.0 failed during the building phase. The exception was:
ExitFailure 1

Answer 1

Hat取决于haskell-src-exts的旧版本。有问题的构造函数似乎在1.14版本中已经消失。

您可以编辑该文件，删除有问题的行并向Hat提交补丁。或者，指定和额外约束：

cabal install hat --constraint haskell-src-exts==1.13.5

将来，您可以通过查看包依赖关系，查找包含相关类型的模块以及查找构造函数来自行跟踪这些问题。这种特殊情况也是可以转让的。