On Tue, Apr 11, 2006 at 09:53:54AM +0100, Simon Peyton-Jones wrote: > Whether it should be in a class is a rather separate discussion. In a > way we already sold out when we allowed seq to escape from the > type-class world. Perhaps deepSeq is worse (because it traverses data > structures) but not obviously.
well, there is a difference there in that 'seq' is unimplementable in haskell, so the design comitee had freedom to implement it however they wanted. however, now that we have seq, a deepSeq is perfectly implementable* in haskell using a typeclass, which is a strong argument for making it have one. * dynamic idempotent issues aside. in any case, if it were to be in the standard, I'd put it in a typeclass and give a haskell translation with a note that implemenations are free to implement optimized versions under the hood as long as the observable effect is the same but you can't count on anything better than the plain old recursive seq definition. John -- John Meacham - ⑆repetae.net⑆john⑈ _______________________________________________ Haskell-prime mailing list Haskell-prime@haskell.org http://haskell.org/mailman/listinfo/haskell-prime