The future of the Haskell98 and Haskell2010 packages

Austin Seipp austin at
Tue Nov 18 16:07:43 UTC 2014

Hello all,

A few weeks ago, I opened up a discussion about a particular GHC bug, #9590.

This bug is concerned with the future of the Haskell98 and Haskell2010
packages, which try to embody their two respective Haskell standards.
They do this by shipping the 'exact library specification' that the
standards have.

In our discussion this past week between me, SimonM, SPJ, Herbert and
Mikolaj, we came to this discussion again since the 7.10 STABLE freeze
is almost here, and it seems to have puttered out.

In this discussion, we came to the conclusion we think these packages
should be removed from GHC for the 7.10 release. To be clear, this was
not a 100% unanimous decision or formal vote; SimonM and I supported
removal, while everyone else seemed to be rather undecided or

Most of the proposed alternative solutions seemed somewhat one-off.
Furthermore, we didn't find a solution that wouldn't either A) require
some amount of GHC modifications (possibly indefinitely into the
future) to support these packages, or B) changing the definitions in
these packages to deviate from the standard.

Instead, we proposed that we instead overhaul part of the GHC users
manual, and clearly outline our deviations from the Haskell 2010
standard library.

To be clear: GHC can still typecheck, compile, and efficiently execute
Haskell 2010 code. It is merely the distribution of compatible
packages that has put us in something of a bind.

Furthermore, we aren't aware of any other compilers/platforms like
ours that try to maintain such stringent separation of these packages,
and furthermore, both of the haskell{98,2010} packages have a fairly
small number of reverse dependencies.

I'd like to hear what people think about this. It seems likely I will
move forward on this by the end of the week unless we face very strong
opposition to this idea, or someone is willing to fix #9590 somehow
for us.


Austin Seipp, Haskell Consultant
Well-Typed LLP,

More information about the ghc-devs mailing list