cabal-install cannot install alex or happy

[TravisCardwell]

Upon installing GHC and cabal-install (via bootstrap.sh), neither alex nor happy are installed. Attempting to install alex using cabal install alex fails with the error message "setup: The program alex is required but it could not be found". Similarly, attempting to install happy using cabal install happy fails with the error message "setup: The program happy is required but it could not be found". Interestingly, both programs can be built and installed using Setup.

Note that solving this issue might be considered a prerequisite to #220.

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Test environment:

• Debian Wheezy (stable); minimal virtual machine
• amd64
• GHC 7.8.2
• cabal-install version 1.18.0.3 using version 1.18.1.3 of the Cabal library
• Alex version 3.1.3
• Happy Version 1.19.3

[23Skidoo]

cabal-install version 1.18.0.3 using version 1.18.1.3 of the Cabal library

Can you try with 1.20 release candidate? I believe I fixed this in HEAD.

[TravisCardwell]

I installed the 1.20 release candidate into the above test environment, and both Alex and Happy install using cabal install without error.

[23Skidoo]

Great.

[YoEight]

Is there a workaround for 1.18 ? I only get that issue on Windows. I can install alex and happy with 1.18 on CentOS for instance.

[TravisCardwell]

I do not have a Windows machine to test on, but I was able to install both alex and happy by not using cabal:

1. Fetch the source. (This is already done if you already tried to install using cabal.)
2. Extract the source.
3. Compile Setup.lhs.
4. Run Setup configure, specifying an installation prefix if necessary.
5. Run Setup build.
6. Run Setup install, specifying --user or --global if necessary, depending on where you are installing.

[YoEight]

Thanks , Building alex and happy without cabal worked after I deleted my .cabal and .ghc