[Haskell] ANNOUNCE: GHC version 7.6.1

Felipe Almeida Lessa felipe.lessa at gmail.com
Thu Sep 6 21:23:33 CEST 2012

On Thu, Sep 6, 2012 at 2:49 PM, Thomas DuBuisson
<thomas.dubuisson at gmail.com> wrote:
> We're getting more meta than Haskell provides cleanly, but all
> significant uses I can currently think of for something like that
> would require universal quantification over types:
> Forall types t.
>   t `notElem` someTypes --> fails (tyUnification t MyType)
> I'm curious what your thinking is here.

I'm developing a EDSL for SQL queries that I'll properly announce
tomorrow.  The idea I have in mind is that this code should not

  delete $
  from $ \table ->
  set table []

You should not SET something inside a DELETE statement.  However,
currently that will typecheck---not because I don't know how to fix
it, but because the types were already messy enough and I didn't
ponder about the tradeoffs.

So I would like to put the above snippet on a test suite that says
"this should not typecheck".  It will serve both as a reminder to fix
it someday and as a regression test.  Of course, I could stick each of
these on a separate file and try to compile it, but that would be a
PITA to setup.  Is this a crazy idea? =P

Cheers, =)


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