Edit report at https://bugs.php.net/bug.php?id=48358&edit=1
ID: 48358 Comment by: dnwake at gmail dot com Reported by: dannel at aaronexodus dot com Summary: SplDoublyLinkedList needs an insertAfterIterator() method or something similar Status: Assigned Type: Feature/Change Request Package: SPL related PHP Version: 5.3.0RC2 Assigned To: colder Block user comment: N Private report: N New Comment: This is ridiculous. Efficiency of inserting and deleting in the middle of the list is the main motivation for using a linked list in the first place. Previous Comments: ------------------------------------------------------------------------ [2011-04-15 21:23:51] omercan at gmail dot com O(n) complexity should be expected from a list data structure along with no array access. The drawback of lists is they lack direct access to the elements by their position. Well, that's not the case with SplDoublyLinkedList because there's array access. So, it's a different implementation as far as it seems. In my opinion, the problem with SplDoublyLinkedList is that the main operations are left to be implemented in the user land, which require iterating over the list in each. This class can be much more valuable if the following operations are included: clear() -> clear all elements remove($value) -> return number of removals b/c $value can be more than 1 sort(Closure $predicate) -> sort without keeping key association swap($list) -> swap with another list or a Traversable instance unique() -> return the unique values in the list, possibly in a new list ------------------------------------------------------------------------ [2010-05-22 13:46:01] 1000235409 at smail dot shnu dot edn dot cn i have encountered the same problem today, after this was modified for 1 year... but i have a solution to solve this problem. write anohter class with a lots of spldoublylinkedlists inside it. however, complex algorithm may be used... ------------------------------------------------------------------------ [2009-05-21 17:02:15] dannel at aaronexodus dot com Description: ------------ The SplDoublyLinkedList is great, but it lacks a way to insert a node somewhere in the middle of the list. One could technically extend the class and provide that functionality, but due to the fact that there seem to be [documented] data members in SplDoublyLinkedList, the only way to do it would be to find the reference node, insert the new node, and move all of the following nodes up one slot in the list, resulting in O(n) performance for an insert. I propose adding an insertAfterIterator() method which would place the new node after the current node the iterator points to. Another option could be an insertAfterArrayKey() method which would act similarly, but would find the reference node via a given array key, which might be a little more straightforward to use in code. Each should probably have an insertBefore*() counterpart as well. ------------------------------------------------------------------------ -- Edit this bug report at https://bugs.php.net/bug.php?id=48358&edit=1