darcs patch: [PROOF OF CONCEPT] build readline package with libedit

[Manuel M T Chakravarty]

Duncan Coutts:
>
> On Tue, 2008-02-19 at 12:01 +0100, Henning Thielemann wrote:
>> On Tue, 19 Feb 2008, Christian Maeder wrote:
>>
>>> In order to avoid several #ifdefs (maybe differently or suboptimal
>>> given) in user sources (to achieve 1.) such #ifdefs (or wrappers)
>>> should be part of the libraries (including the documentation for the
>>> license differences)!
>>
>> Can Cabal-1.2's flag capability manage such a task?
>
> I don't think I understand the problem clearly enough to say. Perhaps
> someone can try explaining it in more detail.

Maybe I am reading this the wrong way, but didn't we say we DON'T want  
to build the readline package with libedit, but rather have a separate  
editline package.  A fundamental reason for avoiding building the same  
library interface with alternatively readline and editline was that  
the license of that package would then have to change on a build per  
build basis.  I think we concluded that (a) that would be confusing  
and (b) is not support by Cabal's package meta information.

Manuel