On Tue, Feb 9, 2010 at 7:34 AM, Kam Kasravi <[email protected]> wrote: > Hi Andy > I had mentioned to Brendan at the last TC39 that you had ported narcissus > and had observed the cost of match. > There is a new global regexp parameter called 'y' which prevents the copy > from occurring. > I've taken a look at narcissus and made some edits adding y to match. Both > Brendan and Bob Clary > have advised on how to get the changes into mercurial on mozilla if you are > not a developer within mozilla. > I can forward you these emails and we could review respective changes if you > would like and its ok with > mozilla. The mozilla bug id > is https://bugzilla.mozilla.org/show_bug.cgi?id=542621
Thanks for mentioning that. Is Narcissus being used for something now? I had to make a ton of changes to get it to work on non-Mozilla engines (v8, JScript). It got stuck on this performance issue due to lack of /y. But adding this would introduce another nonstandard feature. I think the solution depends on if the mainline wants to be standard ECMAScript or not. For non-Mozilla engines, the solution without /y is a bit of a pain. What I would do is change the tokenizer to work line-by-line rather on the code entire string. You will still have quadratic behavior within a line, but if lines are less than 100 characters, it won't blow up with a large program size. This would solve it for Mozilla too of course, so I might just go with that since I want it to be standard ECMAScript. thanks, Andy _______________________________________________ es-discuss mailing list [email protected] https://mail.mozilla.org/listinfo/es-discuss
