Balint Erdi wrote: > On Sep 1, 5:42�pm, Jon Hope <[email protected]> wrote: > >> What I want is to be able to return all the forked_stories and their >> forked_stories for a given Story and I'm finding this very difficult >> since they're all based on the same model. I keep running into dead >> ends. If I can return them to a certain depth as well that'd be great, >> so I've been trying to write a method that accepts a depth parameter but >> the crazy loops are frying my brain. > > As far as I can tell you have an algorithmical difficulty, not one > related to Rails. To get back all the forked stories for a given story > the following code snippet would do the job: > > def fork_tree > forked = forked_stories > forked_from_children = forked.inject([]) do |fstories, fstory| > fstories + fstory.fork_tree > end > forked + forked_from_children > end > > (you can see the whole thing here: http://gist.github.com/179186) > > Note1: This has been tested under Ruby, not Rails > Note2: The method is badly named, since it just returns an array, not > a tree-like structure of all the stories forked directly from the > story or from its children, or grandchildren, etc. > > Hope this helps, > B�lint
Note 3: Unless the whole array has already been loaded into memory, that's horribly inefficient. Nested sets are the way to go here. Best, -- Marnen Laibow-Koser http://www.marnen.org [email protected] -- Posted via http://www.ruby-forum.com/. --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "Ruby on Rails: Talk" group. To post to this group, send email to [email protected] To unsubscribe from this group, send email to [email protected] For more options, visit this group at http://groups.google.com/group/rubyonrails-talk?hl=en -~----------~----~----~----~------~----~------~--~---
