PyR*_*lez 4 debugging haskell compiler-errors hat cabal-install
在这个问题中,我们安装了依赖项Hat
.现在,当我尝试做
cabal install Hat
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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
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帽子取决于旧版本haskell-src-exts
.有问题的构造函数似乎在1.14版本中消失了.
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
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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.