On Thu, Sep 6, 2012 at 10:33 AM, Felipe Almeida Lessa <felipe.le...@gmail.com> wrote: > On Thu, Sep 6, 2012 at 1:05 PM, Ian Lynagh <i...@well-typed.com> wrote: >> * It is now possible to defer type errors until runtime using the >> -fdefer-type-errors flag. > > I don't remember if this was part of the motivation in creating this > feature, but it has a nice use case: asserting on a test suite that > something should *not* type check.
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. Thomas _______________________________________________ Glasgow-haskell-users mailing list Glasgow-haskell-users@haskell.org http://www.haskell.org/mailman/listinfo/glasgow-haskell-users
