presentation of dependencies in the web interface

Ross Paterson ross at
Thu Oct 25 07:48:40 EDT 2007

On Thu, Oct 25, 2007 at 01:17:43PM +0200, Thomas Schilling wrote:
> I presume the final interface should be to give the user a simple way to
> query the dependenies by giving assignments for OS, arch,
> implementation, etc. and then dynamically (yes, using JavaScript)
> updating the dependency list.  It shouldn't be hard to generate the
> necessary code from the Cabal file.  I think the current way is okay for
> now, though.

The pages are CGI output, so those could be extra parameters.

> The main problem with using this representation is, that it assumes that
> flags are only used to let Cabal decide dependencies based on present
> dependencies.  This is exactly the part I would *not* want to use them
> for -- they are meant to be used to enable/disable certain features
> like, e.g., using GTK or WXWindows or building with debugging support.

I don't quite follow you, but it treats optional features (if's without
else's) as not creating dependencies.

> Duncan is currently implementing his proposal to use the 'package(...)'
> predicate to enable specifying different dependencies depending on the
> version of some package.

Is that written up somewhere?

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