Stream: t-compiler/wg-nll

Topic: weekly meeting September 25


pnkfelix (Sep 25 2018 at 19:31, on Zulip):

hi @WG-compiler-nll

pnkfelix (Sep 25 2018 at 19:32, on Zulip):

Sorry I'm running a tiny bit behind

pnkfelix (Sep 25 2018 at 19:33, on Zulip):

let's see, good old Paper triage

nikomatsakis (Sep 25 2018 at 19:37, on Zulip):

so

pnkfelix (Sep 25 2018 at 19:37, on Zulip):

there aren't any nominated issues

pnkfelix (Sep 25 2018 at 19:37, on Zulip):

which .. is a good thing...

nikomatsakis (Sep 25 2018 at 19:37, on Zulip):

there are some unassigned milestone issues though

pnkfelix (Sep 25 2018 at 19:38, on Zulip):

I supposed I could take #54528

nikomatsakis (Sep 25 2018 at 19:39, on Zulip):

@Santiago Pastorino didn't you open a PR with a test case for https://github.com/rust-lang/rust/issues/51269 ?

pnkfelix (Sep 25 2018 at 19:41, on Zulip):

The most "interesting" issues on the unassigned milestone issues are probably #54499 , #54332, and #47184

Matthew Jasper (Sep 25 2018 at 19:41, on Zulip):

I'm working towards being able to do something for #54256, but it's some way off.

nikomatsakis (Sep 25 2018 at 19:41, on Zulip):

Re #47184, I just opened up https://github.com/rust-lang/rust/issues/54570

pnkfelix (Sep 25 2018 at 19:41, on Zulip):

(and #54332 is a subtask of #47184 )

nikomatsakis (Sep 25 2018 at 19:41, on Zulip):

which I think is probably the most significant part of it

nikomatsakis (Sep 25 2018 at 19:42, on Zulip):

I assigned #54332 to @Keith Yeung, since it is a natural follow up to the type ascription PR

pnkfelix (Sep 25 2018 at 19:42, on Zulip):

I think #54570 sounds like fun

nikomatsakis (Sep 25 2018 at 19:42, on Zulip):

I'm working towards being able to do something for #54256, but it's some way off.

do you want to assign yourself, in any case?

nikomatsakis (Sep 25 2018 at 19:42, on Zulip):

I think #54570 sounds like fun

you want to tackle it? I think it's pretty independent from the other pieces

pnkfelix (Sep 25 2018 at 19:43, on Zulip):

I would like to tackle it ... and I think I can probably split my time between that and #54528

nikomatsakis (Sep 25 2018 at 19:44, on Zulip):

maybe assign yourself then?

pnkfelix (Sep 25 2018 at 19:44, on Zulip):

done

pnkfelix (Sep 25 2018 at 19:44, on Zulip):

Keep me honest though.

nikomatsakis (Sep 25 2018 at 19:44, on Zulip):

assuming you tackle that and @Keith Yeung takes on #54332, that leaves some more obscure stuff around constants in #47184

nikomatsakis (Sep 25 2018 at 19:44, on Zulip):

I haven't really thought about it, I have this nervous feeling it might be annoying to handle

nikomatsakis (Sep 25 2018 at 19:44, on Zulip):

maybe the first thing to do is draw up some test cases

nikomatsakis (Sep 25 2018 at 19:45, on Zulip):

maybe I'll assign myself #47184 with the purpose of doing that?

pnkfelix (Sep 25 2018 at 19:45, on Zulip):

I think that sounds like a good idea

pnkfelix (Sep 25 2018 at 19:45, on Zulip):

that, or file a fresh issue

pnkfelix (Sep 25 2018 at 19:45, on Zulip):

with that as the explicit goal

pnkfelix (Sep 25 2018 at 19:45, on Zulip):

(which is sort of a squishy goal, but sometimes its nice to have a fresh issue to look at. This one has a lot of history on it....)

nikomatsakis (Sep 25 2018 at 19:46, on Zulip):

makes sense

Santiago Pastorino (Sep 25 2018 at 19:46, on Zulip):

@Santiago Pastorino didn't you open a PR with a test case for https://github.com/rust-lang/rust/issues/51269 ?

checking, unsure if was that one

pnkfelix (Sep 25 2018 at 19:46, on Zulip):

@nikomatsakis is there anything else you want to discuss that is relevant to the RC2 or the Release? I think we're okay on performance?

pnkfelix (Sep 25 2018 at 19:46, on Zulip):

Because an alternative topic is a Polonius checkin

pnkfelix (Sep 25 2018 at 19:47, on Zulip):

(I feel like a saw a slew of bugs go by discussing the current state of Polonius integration)

nikomatsakis (Sep 25 2018 at 19:48, on Zulip):

well

Santiago Pastorino (Sep 25 2018 at 19:48, on Zulip):

@nikomatsakis it was https://github.com/rust-lang/rust/pull/54367

Santiago Pastorino (Sep 25 2018 at 19:48, on Zulip):

let me see

nikomatsakis (Sep 25 2018 at 19:48, on Zulip):

there is https://github.com/rust-lang/rust/issues/53040, but I guess @Matthew Jasper was interested in it

Santiago Pastorino (Sep 25 2018 at 19:49, on Zulip):

@nikomatsakis so yes, a regression test is up for https://github.com/rust-lang/rust/issues/51269 in https://github.com/rust-lang/rust/pull/54367/files

nikomatsakis (Sep 25 2018 at 19:49, on Zulip):

I'd like to see if we can assign these issues

Matthew Jasper (Sep 25 2018 at 19:49, on Zulip):

Yes, but It's unlikely that I'll get around to it before the next beta branch.

nikomatsakis (Sep 25 2018 at 19:49, on Zulip):

@Santiago Pastorino I know you were looking for something to do, maybe https://github.com/rust-lang/rust/issues/54499 ?

Santiago Pastorino (Sep 25 2018 at 19:49, on Zulip):

:+1:

nikomatsakis (Sep 25 2018 at 19:50, on Zulip):

@Matthew Jasper ah, ok— that's Oct 25 I think, is that because you're generally busy, or because you have a bunch of other things in flight?

Keith Yeung (Sep 25 2018 at 19:51, on Zulip):

assuming you tackle that and @Keith Yeung takes on #54332, that leaves some more obscure stuff around constants in #47184

what obscure stuff were you thinking about?

pnkfelix (Sep 25 2018 at 19:52, on Zulip):

stuff like: "Associated constants in patterns: <T as Foo>::BAR", I think is one example

pnkfelix (Sep 25 2018 at 19:53, on Zulip):

from skimming over the unchecked check boxes in the description for #47184

nikomatsakis (Sep 25 2018 at 19:53, on Zulip):

basically all the things that are unchecked in #47184

nikomatsakis (Sep 25 2018 at 19:53, on Zulip):

there is also things like let Foo::<'static>(22) = bar

nikomatsakis (Sep 25 2018 at 19:53, on Zulip):

I think that would be .. somewhat straightforward to support

Matthew Jasper (Sep 25 2018 at 19:53, on Zulip):

Also <Foo<T, U>>::func(...) (last I checked)

Keith Yeung (Sep 25 2018 at 19:54, on Zulip):

i think it's a matter of being able to extract the turbofish type and relate it to the expression type

nikomatsakis (Sep 25 2018 at 19:54, on Zulip):

in that case it's a pattern, but yes

nikomatsakis (Sep 25 2018 at 19:54, on Zulip):

we do the same thing elsewhere

nikomatsakis (Sep 25 2018 at 19:54, on Zulip):

Also <Foo<T, U>>::func(...) (last I checked)

I believe we handle those correctly

nikomatsakis (Sep 25 2018 at 19:54, on Zulip):

at least, their boxes are checked, so if you have a counterexample, I'd like to see it :)

nikomatsakis (Sep 25 2018 at 19:55, on Zulip):

@Keith Yeung in particular, we have a "pattern type ascription" node already, and I think we can use that

nikomatsakis (Sep 25 2018 at 19:55, on Zulip):

I should break out some more subissues perhaps

pnkfelix (Sep 25 2018 at 19:56, on Zulip):

I just revised the check marks in the check boxes slightly

pnkfelix (Sep 25 2018 at 19:56, on Zulip):

to not check off things just because they have subissues broken out

pnkfelix (Sep 25 2018 at 19:57, on Zulip):

But maybe I misunderstand the goal here: @nikomatsakis , were you hoping to close this issue once there was coverage of the remaining cases via broken out subissues?

pnkfelix (Sep 25 2018 at 19:57, on Zulip):

(because that is a scenario where I would understand checking off those boxes)

nikomatsakis (Sep 25 2018 at 19:57, on Zulip):

I was checking this with subissues, yes, because otherwise it's not clear

nikomatsakis (Sep 25 2018 at 19:57, on Zulip):

which one is "responsible"

Matthew Jasper (Sep 25 2018 at 19:57, on Zulip):

@Matthew Jasper ah, ok— that's Oct 25 I think, is that because you're generally busy, or because you have a bunch of other things in flight?

I'm trying to get other things done first. I don't really know how long they will take

nikomatsakis (Sep 25 2018 at 19:57, on Zulip):

I broke out https://github.com/rust-lang/rust/issues/54573

nikomatsakis (Sep 25 2018 at 19:58, on Zulip):

(however, I am fine to not check off the subissue boxes)

Matthew Jasper (Sep 25 2018 at 19:58, on Zulip):

at least, their boxes are checked, so if you have a counterexample, I'd like to see it :)

https://play.rust-lang.org/?gist=bf45334d12da6430c0a36465973e2c1a&version=nightly&mode=debug&edition=2015

nikomatsakis (Sep 25 2018 at 20:00, on Zulip):

d'oh! good catch then

nikomatsakis (Sep 25 2018 at 20:05, on Zulip):

ok I filed https://github.com/rust-lang/rust/issues/54574 for that (and added to #47184)

nikomatsakis (Sep 25 2018 at 20:08, on Zulip):

ok well I guess that's it for today? We've got a lot of issues filed now...

pnkfelix (Sep 25 2018 at 20:13, on Zulip):

thanks everyone!

Last update: Nov 21 2019 at 15:15UTC