How about having hashCode() on infinite sequences drill down into the composite infinite sequences until we arrive at the generative function? Given that values are generated on demand, the generators themselves can be compared.
To take from your fibs example: hashCode(iterate f x) = hashCode(x) + (37 * (hashCode(fn) + (37 * base- iterate-hash-value)) (Apologies for infix representation.) Lazy-sequence functions that wrap the iterate call would have their own hashCode() function call iterate's in a composite fashion. This way we avoid iterating over the values generated and instead derive unique values for unique sequences. On Oct 28, 3:55 am, John Harrop <jharrop...@gmail.com> wrote: > and it's not hard to guess, and then prove, why: > > user=> (defn fibs [] (map first (iterate (fn [[a b]] [b (+ a b)]) [1 1]))) > #'user/fibs > user=> (take 10 (fibs)) > (1 1 2 3 5 8 13 21 34 55) > user=> (.hashCode 12) > 12 > user=> (.hashCode "foo") > 101574 > user=> (.hashCode (take 10 (fibs))) > -1796812414 > user=> (.hashCode (fibs)) > <hangs> > > Probably the seq .hashCode should consider only the first N elements for > some maximum N and if two longer (or even infinite) sequences collide so be > it. --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "Clojure" group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en -~----------~----~----~----~------~----~------~--~---
