On Sun, Jan 24, 2010 at 3:12 PM, Stephen Tetley <stephen.tet...@gmail.com> wrote: > Doesn't the simply typed lambda calculus introduce if-then-else as a > primitive precisely so that it can be typed? > > Its not an illuminating answer to your question and I'd welcome > clarification for my own understanding, but I don't think you can > solve the problem without appealing to Haskell's built-in > if-then-else.
Yes, encoding data types as pure typed lambda terms requires rank-2 types. I'd recommend that Dušan Kolář start giving types to all these functions. However, it will, eventually, be necessary to go beyond Haskell 98 to give the appropriate types. _______________________________________________ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
