2011/5/3 Manuel M T Chakravarty
Interestingly, today (at least the academic fraction of) the Haskell community appears to hold the purity of the language in higher regard than its laziness.
I find Greg Morissett's comment on Lennart Augustsson's article pro lazy evaluation very interesting: http://augustss.blogspot.com/2011/05/more-points-for-lazy-evaluation-in.html... What I find interesting is that he considers (non-)termination an effect, which Haskell does not manage to control like it does other types of effects. Dependently typed purely functional languages like Coq (or Agda if you prefer ;)) do manage to control this (at the cost of replacing general recursion with structural recursion) and require you to model non-termination in a monad (or Applicative functor) like in YNot or Agda's partiality monad (written _⊥) which models just non-termination. I have the impression that this separation of the partiality effect provides a certain independence of evaluation order which neither ML (because of side-effects) nor Haskell (because of non-strict semantics) manage to provide. Such an independence seems very useful for optimization and parallel purposes. Dominique