lcd wrote: > On 21 March 2014, Cade Forester <ahx2...@gmail.com> wrote: > > > How about separating it from sort()? That is, an uniq() > > > function that would remove duplicates from an already sorted list > > > (results would be undefined if the input list is not sorted). That > > > would be consistent with how uniq(1) works on UNIX. > > > > This patch add uniq() function. uniq(list) will remove copies of > > repeated adjacent items > > There is a problem with this patch: it removes the duplicates on the > fly, so if the comparison function fails on the second or subsequent > call the list is still modified. In contrast, sort() restores the list > to the initial state if the comparison fails at some point. > > I'm attaching bellow my attempt to a fix. I also merged f_sort() > and f_uniq() in a single function, and made some minor optimisations. > > On a related topic: adding an efficient "stable unique" would be > relatively straightforward too, using plain red-black trees. Now, > red-black trees are implemented as a header (namely sys/tree.h) on *BSD, > but not on other systems. Any comment on the preferred way to handle > this? I'd suggest testing for the existence of sys/tree.h in autoconf, > and also including a stripped down copy of it from, say, OpenBSD, for > the systems that don't have it.
There are a few problems with this implementation. The li_prev pointer is not updated. When the first item is not a list the error is for sort(), even when uniq() is used. -- It is too bad that the speed of light hasn't kept pace with the changes in CPU speed and network bandwidth. -- <wie...@porcupine.org> /// Bram Moolenaar -- b...@moolenaar.net -- http://www.Moolenaar.net \\\ /// sponsor Vim, vote for features -- http://www.Vim.org/sponsor/ \\\ \\\ an exciting new programming language -- http://www.Zimbu.org /// \\\ help me help AIDS victims -- http://ICCF-Holland.org /// -- -- You received this message from the "vim_dev" maillist. Do not top-post! Type your reply below the text you are replying to. For more information, visit http://www.vim.org/maillist.php --- You received this message because you are subscribed to the Google Groups "vim_dev" group. To unsubscribe from this group and stop receiving emails from it, send an email to vim_dev+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
