On Sun, Jan 4, 2009 at 5:51 PM, Jason Wolfe <jawo...@berkeley.edu> wrote: > > That does satisfy my requirements as a lazy stack data structure. > However, it does so by adding an inner level of cons objects; this is > more or less equivalent to just calling (delay) on each level of the > seq and then having to explicitly (force) each time an element is > extracted.
Except that I introduce no new object at all. I don't create any seq or delay object. Every object I used was given to me from the user of 'push-seq' function, so I'm not quite sure what you mean. > With either workaround, the built-in seq functions are no > longer directly applicable. I can't call filter directly on an mstk, > for example. This would be true of any compound data structure built out of clojure collections. 'filter', 'map' etc. don't automatically traverse trees, graphs, or other nested structures. But a function that returns a lazy seq over an mstk is pretty easy: (defn mstk-seq [mstk] (lazy-cons (single-peek mstk) (single-pop mstk))) I think you'll find this has the same laziness profile as the raw calls to single-peek and single-pop I presented earlier. --Chouser --~--~---------~--~----~------------~-------~--~----~ 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 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 -~----------~----~----~----~------~----~------~--~---
