18:35
<peetk>
went over notes for the proposal review and tried to put all the action items in the conclusion. repeating those here in case anyone forgot what they committed to: -PKA will check with ACE on the status of JSON.parseImmutable. -RBN will take a new look at RegExp Buffer Boundaries in light of CDA’s belief that it may be a very important security feature. -SHS will reach out to KOT about the withdrawability of dynamic import host adjustment. -KM will check with SYG about Atomics.pause, and possibly bring it for Stage 4 next meeting.
18:43
<Chris de Almeida>
I also said we'd look at 'Atomic Operators' to see if there should be a clear prioritization from a sec perspective (vs 'buffer boundaries')
18:48
<Michael Ficarra>
regarding the RegExp proposals, I really want to get Clément Pit-Claudel and/or Aurèle Barrière from EPFL to present their work on a linear implementation of JS RegExps which is uniquely possible among the major programming languages' embedded RegExp feature sets
18:49
<Michael Ficarra>
being able to have a linear implementation is an incredibly valuable property that I would not want to lose by accident, even though implementations in major engines today do not take advantage of it
18:50
<Michael Ficarra>
that said, I am quite confident that buffer boundaries would not cause an issue, but I want to be very careful with future and in-progress RegExp proposals
19:10
<Chris de Almeida>
any concerns w/ the 'Atomic Operators' proposal in this regard?
19:11
<Michael Ficarra>
you're going to have to ask the experts about that one
19:17
<iain>
V8 has an experimental implementation of a non-backtracking allocator here. My vague impression (but somebody from V8 would know better) is that it mostly works, but it's enough slower than the backtracking implementation in non-pathological cases that it only really makes sense to use a backstop instead of the primary implementation, at which point that's a lot of extra complexity to expose just to cushion the blow for people who write bad regexps.
19:45
<rbuckton>
Is it that much slower than positive lookahead? Positive lookahead is already atomic.
19:46
<rbuckton>
Ah, nm. Thought you were referencing atomic operators, not linear regexp in general
20:43
<Michael Ficarra>
btw for anyone looking for more info about their work, here's their materials from when they presented to TG5: https://github.com/tc39/tg5/blob/main/agendas/2025/2025-08-27.md