RE: [VETO] Revert buffer patch

-----Original Message----- From: xemacs-beta-admin(a)xemacs.org [mailto:xemacs-beta-admin＠xemacs.org]On Behalf Of Ben Wing Sent: Saturday, November 17, 2001 10:52 PM To: Andy Piper Cc: Andy Piper; Stephen J. Turnbull; Paul Krause; XEmacs Beta List Subject: Re: [VETO] Revert buffer patch replace the regular revert-buffer function with this: 1. remember the file size when you revert. 2. next time you revert, if the file size has changed, and the new file size is greater than some arbitrary value [e.g. 1 megabyte], do what we regularly do. otherwise: 3. create a temporary buffer. 4. disable change hooks in the buffer, e.g. bind them to nil. 5. do all the regular revert-buffer stuff, up to but not including after-revert-hook, but with the results going into the temp buffer. 6. compare to the original. 7. if no change, do nothing. otherwise, stop disabling the change hooks, copy the new buffer into the original, run the after-revert-hook. 8. if you want to optimize further, instead of just copying figure out how much text at the beginning and end haven't changed, and only copy the middle section that has changed. this might require c support. insert-file-contents already has code to do this kind of checking. 1 + 2 are only there as an optimization. deleting those steps won't make things any less safe but might temporarily use a large amount of memory in a situation where the optimization of 3 - 8 is unlikely to succeed. Andy Piper wrote: > > > what are you trying to achieve? i explained how to optimize away > > after-revert-hook and after-change-hook. this should eliminate > > all slowness > > you're complaining about. > > Ben, > > Please add some more words to your explanation so that it makes sense to > lesser mortals like me. > > Thanks > > andy