On Jun 13, 11:07 pm, James Reeves <weavejes...@googlemail.com> wrote: > For instance, lets say I want to return a lazy list of all the lines > in all the files in a directory tree: > > (use '(clojure.contrib java-utils > duck-streams))
When clojure.contrib releases version 1.0, that might be an option. > (defn all-line-seq [dir] > (mapcat read-lines (file-seq (file dir)))) > > Since file-seq, read-lines and mapcat all lazy, my final result is > lazy as well. Seems to me that unless you completely consume the sequence, it will leak a file handle. > > Is file-seq recursive? I'd figured it just returned the flat contents > > of a directory. > > Yep, it's recursive. OK. Even so, the implementation in terms of super-lazy-seq shows the power of that macro. Mostly, I'm doing quite a few things with I/O that require custom next-item-in-seq generators for the records or other objects returned, for which it's coming in real handy. In those circumstances lazy-seq saves the bother of doing a loop/recur in everyplace that consumes some records, and super-lazy-seq in turn lets me still use a loop/recur style in the one place where the code extracts and grovels over the records one by one. --~--~---------~--~----~------------~-------~--~----~ 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 -~----------~----~----~----~------~----~------~--~---
