[Haskell-cafe] Re: Cabal + yi + alex problem.

[Ben Franksen]

Austin Seipp wrote:
>> For that matter, "ghc-pkg list | grep -i alex" doesn't list anything,
>> after I cabal-installed it.  How does cabal verify the prerequisite alex
>> version?  (Or does it?)
> 
> ghc-pkg lists libraries that are registered with the ghc package
> manager (globally and locally); alex is simply an application, not a
> library, so there's really nothing for GHC to register. As for telling
> what version is necessary, I haven't the slightest.

Slightly OT, but this division of work between cabal and ghc-pkg has always
looked strange to me. Cabal knows better what meta information to store
about a package, library or application. IMO the package database should
reside with cabal; implementations like ghc or hugs or whatever could query
cabal about the information they need (e.g. for building).

Cheers
Ben