[Haskell-cafe] Cabal install fails, don't understand why

[Henning Thielemann]

On Fri, 29 Mar 2024, Volker Wysk wrote:

> I've migrated my HsShellScript library to Cabal 3.0 and now I get an error
> when I try to install it:
>
> -----snip-----
> desktop /usr/local/src/hsshellscript $ cabal install --user
> Wrote tarball sdist to
> /usr/local/src/hsshellscript/dist-newstyle/sdist/hsshellscript-3.6.0.tar.gz
> Resolving dependencies...
> Error: cabal: Cannot build the executables in the package hsshellscript
> because it does not contain any executables. Check the .cabal file for the
> package and make sure that it properly declares the components that you
> expect.
> -----snip-----
>
> I don't understand this error message. Why does it think it should build
> executables? There aren't any. It's a library only.


Things changed from Cabal-1 to Cabal-3. Old behaviour is retained by 
'cabal v1-install'. Today, 'cabal install' is synonym for 'cabal 
v2-install' and refers to Nix-style builds.