[Haskell] Re: Trying to install binary-0.4

[Simon Marlow]

Ketil Malde wrote:
> Simon Marlow <simonmarhaskell at gmail.com> writes:
> 
>> http://hackage.haskell.org/trac/ghc/wiki/PackageCompatibility
> 
>> It's been helpful for me to write all this down, the issues seem much
>> clearer.  However, I don't see an obviously best solution.  For me
>> proposal 4.2 (see the wiki page) looks the most promising, but it
>> doesn't provide complete backwards compatibility, so I imagine there
>> will be people who disagree.
> 
> The section "The problem of lax version dependencies" refers to
> "Solution 3", which doesn't seem to exists. Presumably "Solution 2" is meant?
> 
> Wouldn't keeping "base-2.0" and rebranding "base-3.0" to
> "foundation-1.0" (which might be listed as "Solution 2.1") solve this
> issue? 

This is actually what proposal 4.2 is about.  But note that in order to 
keep base-2.0 around you need to either compile up a complete copy of it 
and all the packages that depend on it (proposal 2, a non-starter IMO), or 
allow package re-exports (proposal 4).  Maintaining an exact replica of the 
base-2.0 API is impractical (proposal 4.1), so what we'd actually have is 
base-3.0 (proposal 4.2).

Cheers,
	Simon