I believe the point made by Ariel about non-local access is to be taken in high consideration. As he said, the gain obtained by caching very small expressions may be lost due to non-local variable access. So changes should be done only where a speed improvement can be achieved and verified.
The trim() case was solved and the problem was not about caching of the regular expression but maybe a too complicated RegExp for the task. A simpler one was enough. As I said, I was following the trim() thread, spotting some ideas on what could be wrong. So speed is not a concern, readability maybe, if it doesn't slow down code execution. Diego On 2 Feb, 17:19, John Resig <jere...@gmail.com> wrote: > It depends - if there's a considerable amount of duplicate code it > would be good to cut down on that (using the same regex over and over, > for example). > > --John > > On Mon, Feb 2, 2009 at 8:40 AM, Ariel Flesler <afles...@gmail.com> wrote: > > > Why patch it, John ? there's no speed gain and I actually think it'd > > make things slower. > > If you save the regex in a var within the upper scope, each access > > will take longer than if it were 100% local. > > > -- > > Ariel Flesler > >http://flesler.blogspot.com > > > On Feb 1, 10:09 pm, John Resig <jere...@gmail.com> wrote: > >> Ah, ok. I suspect that some of that may be in Sizzle. Patches are welcome! > > >> --John > > >> On Sun, Feb 1, 2009 at 2:14 PM, Diego Perini <diego.per...@gmail.com> > >> wrote: > > >> > John, > >> > well I did some small test with: > > >> > /\s+/ > >> > /\\/g > > >> > and it seems there is no appreciable speed gain that I could measure. > > >> > I spotted those shorter RegExp because I saw they are re-used at least > >> > 4 or 5 times in current jQuery. > > >> > Thanks to jdalton for the link and explanation. > > >> > Diego > > >> > On 1 Feb, 15:53, John Resig <jere...@gmail.com> wrote: > >> >> Is there any appreciable speed-up to caching RegExp that are that > >> >> small? I wasn't able to find any when I looked. > > >> >> --John > > >> >> On Sun, Feb 1, 2009 at 7:58 AM, Diego Perini <diego.per...@gmail.com> > >> >> wrote: > > >> >> > I did have a quick look through the code and see that most of the > >> >> > (small) regular expressions are not cached and referenced but defined > >> >> > in-line in the conditionals/replacements. > > >> >> > For example these are repeatedly used in various place: > > >> >> > /\s+/ > >> >> > /\\/g > >> >> > /\?/ > > >> >> > I believe there are improvements in both speed and readability of code > >> >> > by caching them compiled. > > >> >> > Is there some reason I don't know in not defining some constants like > >> >> > TRIM, SQUEEZE, ESCAPE etc... ? > > >> >> > Diego- Hide quoted text - > > >> - Show quoted text - --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "jQuery Development" group. To post to this group, send email to jquery-dev@googlegroups.com To unsubscribe from this group, send email to jquery-dev+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/jquery-dev?hl=en -~----------~----~----~----~------~----~------~--~---
