Re: Extending the dependency syntax

On Thu, Jul 28, 2005 at 02:23:55PM -0700, Isaac Jones wrote:

"Simon Marlow" writes:

...

So here's a strawman proposal to address some of the use cases raised recently[1] that Cabal doesn't currently support well. This is just a first attempt; I expect we'll need to make changes or start over if we discover cases that it doesn't handle.

(snip proposal)

Lots of this is stuff I've been wanting to ad at some point. I think that rather than overloading the build-depends field, we should add a new field for tool dependencies; otherwise, we could get name conflicts between the two and such.

Agreed; currently we know that everything in build-depends is a cabal package we need to depend on, which makes things simpler.

...

build-depends: base>=1.0 (ghc>=6.4 || ghc>=6.2 [ghc62] || hugs-any [hugs])

For libraries we(Debian)'d need to be guaranteed that the left-most of the satisfactory options had been chosen. Otherwise, having built a library which "build-depends: foo || bar", I don't think we could work out whether we should depend on libghc6-foo-dev or libghc6-bar-dev (or equivalent for another impl). Thanks Ian