Haskell 2010 libraries

[Simon Marlow]

On 30/04/10 23:52, Felipe Lessa wrote:
> On Fri, Apr 30, 2010 at 09:37:39PM +0100, Simon Marlow wrote:
>> I like the picture where we have a small base, lots of independent
>> packages, and one or more haskell20xx packages that re-exports all
>> the standardised stuff from the other packages.  This arrangement
>> extends smoothly, the only problem is that haskell20xx overlaps with
>> the other packages.
>
> I wonder how much pain will there be when Haskell 2011 comes out.
> Some packages will depend on haskell2010, and others on
> haskell2011.  Will they integrate and compile fine?
>
> If haskell2010 is a metapackage that says
>
>    Depends: base == X.Y.*
>
> and haskell2011 is another metapackage that says
>
>    Depends: base == Z.W.*
>
> then I think we're going to have big problems.  Sorry if this is
> a resolved issue. :)

That won't be a problem, for the same reasons that we can happily mix 
packages that depend on base-3 with packages that depend on base-4 right 
now.

That is, unless Haskell 2011 decides to make some incompatible changes 
to datatypes or classes, as Ian pointed out.

Cheers,
	Simon