.Net Foundation Design Reviews, 13 Jun 2019

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From YouTube: .NET Design Review: Nullable Annotations

Description

We're trying to finish reviewing the nullable annotations for System.Runtime.

A

All right, so we are now live if I didn't screw. It up looks like it all right so.

B

Oh pinion so far, so nothing is being marked knowable here.

C

That's because it's everything is better.

D

C

Type as either is like the arguments of the you know, the constructor can't be null and everything that takes a T. It's subject to you know all the generic stuff, so yeah.

B

I was good. This will be hard.

C

E

C

E

C

Based are either really easy or really hard. There's nothing in between Jeremy.

F

Are really quiet? I think you have something in.

E

F

E

Looks like it throws if the I producer consumer collection is null, so those should be how those are not knowable. Okay, never mind. I'm. Looking for question marks that bang prepped.

G

Right and then copy to add to any will Pro. Presumably if the collections of null.

C

Yeah I, don't think they'd accept nulls inside the collections.

G

And will return an empty array for to array.

C

Now we never return empty range from two right, so.

B

Copy two is gonna, be a bit interesting because say that I instantiate blocking collection, what tea is stirring, not malleable stream it just strange drink coffee to noble string array should succeed. Corrupt.

F

But what is not yeah right so so you're.

B

Saying that the tea have.

F

You more relaxed yes,.

B

Because it's kind of old, not necessarily because if T is a value.

H

Tilings really, but so so in implicit.

B

In my question is an assumption, maybe my assumptions wrong. Someone can tell me it's it's possible to instantiate a blocking collection of string and its pulse can't instantiate a blocking collection of string. Question mark correct. Yes,.

I

B

They're they're both the same thing under the covers right. Well: okay, yes, you're.

C

Saying the question is you want to do basically blocking collection of string, dot, copy to strength, strength, question, mark array, correct.

I

Because that's fully yet.

C

Well, the thing is that there don't have any way to sit to tell the compiler that copy two isn't gonna, try and bead an element out of that array. Right.

B

But some semantically, like from.

C

Yeah yeah but I'm, saying like from the call site.

B

It should work because it's like you, said it's out it's right on link. Well, we don't have any way to express his is that a deficiency in the system that needs to be addressed for workshops, I, think it's kind of a limitation of the THAAD system, I.

C

Think it's in that case, you use explanation.

C

A

Kind of what they have that future I mean.

E

That I think the question is: do we need to know? Is it worth having another attribute to describe that this one should accept a variant on that I. Basically,.

J

It would be an attribute to express variants that normally isn't there knitting.

F

Sales to me like it, should be equivalent to the Alalu like something along them, finding more expression from what energy yeah I guess.

B

What I'm saying is this scenario logically, should work? What does the developer have to type in order to make it work, and is it unreasonable to expect a developer to have to talk about.

J

J

Regardless of whatever the solution that we would come up with in Winship, there's not enough time for its connection.

H

You just make something like a lot more type of fee or something I wouldn't possibly. I went.

J

Saying just right having everything we could potentially do something like that. I would say that this is would be a post yeah, but if we can ship the alternative setup button, my book.

H

Make it work here, it's more than white ship, the action, so the compiler like that it.

B

Doesn't help anybody but.

H

If we want well.

B

If we were to do this later, theoretically, would the API still look like this I guess it sounds like the answer is yes, so we should just.

J

B

J

We would do we couldn't break the existing API right likely, whatever we do has to work for this. Okay.

B

Yeah, maybe it's just a bunch of custom activity had slept around an API and I. Can the developer at least work around it for now.

C

It sounds like the answer is yes,.

B

C

Of saying you know, C dot copy to foo, they say C, dot, copy to foo, exclamation point okay,.

G

So it's a one character, change, yeah and then, if we added the ability to annotate variants later, then presumably we'll also get a new warning attention warning waves that says: hey would.

E

It be food hang or would it be a cast to keep bang.

C

Bang bang I mean you could also you could first cast it, but to cast it you would still need to add exclamation point.

E

Would say that I promise the array isn't null, but the problem is. The array is already known.

K

As elavil wanders.

E

The bang is knowable suppression, often just in general.

C

E

C

Problem in this case is your kiss is the type mismatch going from a string question mark array to a string array, and so the bang on the foo basically says ignore warnings related to the type of this thing. Okay,.

E

That's better than I thought it was yeah.

B

That seems pretty straightforward them. Okay, yeah I didn't want a rathole on this too much I just want to make sure like this is feasible. Yeah.

C

I mean the attributes that that we have that are you know that are currently being buzzed the compiler and that we plumb through core lab they're all sort of top level. We don't have anything that deals with annotating the T. That's part of you know an array or whatever other than constraints like that.

G

And you also have the case of like what, if it's a t array, multi-dimensional array, and then you want to annotate you, but.

F

You only only want to entity because you can already imma take the outer arrays right, so only the T is actually relevant. So probably a long move, type of tea or something I mean that's what I'm thinking but I you know have to think about so much cases. That's probably worth philocan languages. Anything right this having this horse injury in it. So far, I.

A

Mean you say red hole but, like the whole meeting is a rat hole. I think that's kind of the point of these.

A

So that means maybe the API review is actually fast, because it's all generic, so I'm not much for us to do.

G

Or so, I have one question real, quick on take from any so normally we annotate for if this was a reference type, we would annotate T as not null when condition is there any annotation for that for when it's purely generic, and we want to say like if this is a reference type than item you know, I mean.

A

Like the Elwood, so the out had an attribute for either case this.

C

Doesn't have the attributes, but on take for many there's a may be no and false on that.

G

C

A

Yes, I feel, like I, probably have to do some coding at some point to actually feel the introduced I'm, not like them right now, when you do it different attributes of just hangs.

B

Oh boy, Oh doesn't sorry out now.

B

How did you say that work Steve when you have zone.

C

We have we have a few attributes that we can apply in these situations and for generics generally, when you have a generic out, t will apply if any in a try. Pattern will apply an attribute, maybe know when false, but which basically actually I, just realized. It's not gonna work here the attributes bogus because this doesn't return this returns in it.

L

C

So we don't have any way to express this. Okay.

G

C

Will be to leave these attributes and they're basically.

C

Well, I'll have to add, maybe no basically so well it'll be attributed with. Maybe dull and people are gonna have to bang when they use it.

M

Or do a tech tour now that will never fail.

E

It may be that the compiler needs a improve detection, that it should be angry of that attribute, supplied on a non boolean return, but.

C

Well, yeah big part of the part of this. It very well might part of the problem. Is we added all these attributes several weeks before there was any compiler support so.

F

C

F

L

Do like you know, other disable.

B

On just for members return so off to the API. Is that a null ability in at all yeah.

L

Please make them.

B

Are movies because it seems like the right.

D

Date, many Romans and I mean.

C

We could it's a question of more warnings, you know more false positives or false negatives, which is worse. It.

G

It might be just worth discussing with the compiler team later like for post video. If there's a way, we can better express it common annotations like not null when negative or positive, but.

A

You have the option to just of this one parameter and based on how you put the bregma, you could have top just the one parameter. Yes, it which doesn't seem like reasonable right.

C

A

C

Same thing, in other places, like you know, methods that are have to be defined to return nullable, but have a boolean that indicate whether it will actually be knowable or not like typed get type, there's a throw on or argument, and if it's true it'll never return null. If it's false right.

N

C

Might return, and so today, you're just always gonna have to null check the result. This is very similar right. This is regardless of what this returns. You're gonna have to know, check the results. Alternatively, if we made it oblivious, you won't have to know check the results, but you also might try and dereference a when it's done.

J

I'm, certainly more safe than the letter making.

B

The parameter, oblivious, yeah.

J

I

Rather, not making.

G

I

They can okay.

G

I'd much rather get the additional warnings and safety and have to bang them away. Then scatter pragmas on in visual parameters in the code base, so.

B

C

G

Do that when they have the same thing, so what we.

C

Tried very very hard not to use available disabled the only place that we used it, as far has been in a place where we could not. The user experience was so bad that we had to use it. So.

B

How does this method signature change then.

C

There's gonna be a maybe Knoll of the out tea item. Okay,.

G

And maybe in the future, if we work with a compiler, we could get another attribute that could replace, maybe null to express it correctly because.

C

I imagine there's a.

G

Few cases like this that would be effectively maybe know when negative.

C

Things I mean we yeah. We had talked about having a changing, maybe no when won't to instead be maybe no when object, and the compiler would allow you to use any cause, any constant expression that you could put in there, the Union metadata and then, if the compiler saw that value used as a constant in comparison like.

C

If try take from any equals negative one, then it would be able to compare that against the constant that was in the attribute, and so it would apply not just to true and false, but to things like negative one, and so that was scoped out. But you could imagine that being added subsequently and then it should be a non-breaking change to update the the attributes in that direction, because it would just mean that people have more exclamation points than they need right.

B

Yeah I'm just looking on dictionary to see how how it looks there as an example: okay,.

C

Dictionaries, yeah dictionary is a case where it's a pool and sometimes maybe no and false.

C

I'm actually interested to see we have a PR I, just finished are about to finish absorbing the compiler changes that enable most of the attributes in core lip I'm about to do the same in core FX that I'm curious to see if it Flags these mistakes, I made with maybe no and false on something that doesn't return. A bool.

A

I mean I would be shocked if you didn't, because it's we're doing a large API services.

N

Okay and it just copy-paste the most part.

A

Bag I think looks fine to consider when we just stand at the.

L

Typewriter key yeah has a sample from from looking at the arcade of the PR. It doesn't seem like it flocks those cases all the fields. All the deals are green.

G

Traffic and try to take don't have the same.

D

Column because we got maybe know when false yeah.

B

Yes, what is with those attributes, show up in the tip here Naga to doesn't support it. Yet I can.

A

Turn them off as soon as I turn them on, like.

L

The to never comes back.

F

L

Everything is so tributed on source, so you can give year two years you can go into source of Batman. We showed you.

B

Well, but these haven't been checked in yet no.

L

Yeah, this is know where Tiki.

K

A

No, no, no yeah! No! No.

K

That's already been changed.

K

A

Let me actually write as long as I think there's two bucks I have to fix the attributes and then not now.

L

No I already fixed it. You just need to get in yeah.

A

The UPS no more is.

C

Sorry, which pr's not merchants auto.

L

One forget API to understand.

I

I

G

And compare anole is Depot compare craft great.

G

G

E

E

E

Did we change concurrent dictionary to accept null in core because it looks like the framework throws if it's null, but their errors go for the picker.

K

G

So what have thought that the first constructor forwards to the second one, with no like most of our API, is do I.

C

Mean that's exactly what it does.

E

I see in framework concurrent dictionary of intent, comparer calls an internal constructor without doing a null cascade and then in that internal constructors, as if compares null for argument no exception, comparable series.

L

Here also called to an internal constructor, but we do the default. The comparator is no.

L

E

Yeah cool okay: do we care this.

M

Framework didn't allow no.

C

I, don't think so. Yeah.

M

G

Annotations, don't work for framework well, not officially supported.

B

For framework, but it sounds like we just want the the more relaxed of the two anyway great. Why.

G

I mean why you're only going to be using mobile annotations with core and officially supported scenarios. So why not just follow what core does? Okay sure.

N

J

Surely kill is painful, sounds like you just signed up as a sim ship. Another version of the premise of Windows.

O

I'll be elsewhere.

O

C

C

Just answer your question: Jeremy, it was fixed for dotnet core Oh as a bug fix.

B

By the way, regarding the variance thing that I mentioned earlier, in theory, things like add value, Factory and update value Factory, the T key argument could be to keep pushing more because, in theory, nosal out there, because it's no, it's not a key is constrained to be not no, no no I mean add value Factory, not a value Factory. Why shouldn't I be able to pass a delegate that has T key kept question mark as its input perimeter right, because once it's gone.

G

B

G

B

Basically, covariance sure.

F

B

It's just something that we would, if, if the language support for it right now doesn't exist, maybe it's just something that can be thrown onto the pile just because it's it's something that ideally should just work that.

C

Said I'm having trouble imagining a situation where you would actually want that in this particular case, it's super rare to reuse. One of these functions across usually they're, just lambdas, so you'd be adding extra question marks into your lambda that were unnecessary. Well.

B

If you are taking T key and passing it into other api's that are typed as allowables, then it would be easier just to declare the lambda once ahead of time. There's.

G

Also, probably some like WPF cases with notify property changed where you might be reusing, a single thing and checking the name as some people do. Yeah I.

B

Mean it's probably a bit esoteric but yeah.

E

They may, in your case, if the lambda said it doesn't accept null, it's still allowed to call functions that say that they do accept null it's the other way that requires bangs, yes, you're, right, nevermind, okay,.

J

And their funk, I believe you should be able to if T value is malleable, I believe you should be able to tell factory.

G

That returns not malleable in it right. It's just you can't bind a a non notable delegate to a notable Tiki was malleable and you has to have fun, but it doesn't actually.

A

I'm fine, thank you.

G

But I think he has to use the arrow keys or gets the high DPI. Sir. Well.

A

If I can thus cooling down works 12 in destiny,.

A

Is a bug that I can't claim this is a bug in Destin in a jar.

G

All right so, okay and then we said to array returns empty yeah empty, not null right. If the collection, something yeah.

C

G

C

It we have to array returning null anywhere in the framework. That's a bug.

C

P

Did any of the dry and thank you.

P

C

I get value, try remove both have maybe dull and false.

P

C

P

Out and then he.

P

C

No, no, this is concur Kiki.

C

This is dictionary yeah, that's fine! It's constraint! You.

P

Can trained and then they'll actually throwing me pass and all it does not work No.

I

P

But if you would repeat maybe.

C

C

St. per stack, try peek, try pop.

E

And our our rule is, if you use exclamation marks to put garbage in you'll get garbage out and we don't care right right, though, in current queue you can you can force in queue and null and then the API would be lying, but you're the one who cheated correct, yeah.

P

I mean there's it's not. We don't change anything in the run time. Okay,.

E

Just making sure again.

C

Otherwise, we'd have to basically say that every opposition was knowable on everything.

A

So try pop range. What's the behavior like is the expectation that the array must be fully filled and if it's not the case, you return what.

C

It returns the number of items that are filled then.

A

It means the array, so what are the other ones? You set them to knowledge, just don't let them you don't need unchanged. The content we.

C

Don't change the content.

C

So the typical use case would be you, you have your pre-allocated array and you just continually pop into it right.

G

C

You know it tells you how many a filter, I.

G

Think we should generally view that cases it's no different than span in that you can only fill the slide. You'll only touch this the slice of whatever this.

D

Pan is viewing your they make sense, I'm just thinking of.

A

Like you know, it's the Ansari, if it would have been, we said the other ones to know and that's another example where we can't really express also lieutenant price, but it seems like in this case it's just what, whatever the caller said, be ready to ride a day, and is it everything to ones or zeros that'll be their call they're here.

N

What's their instance.

A

What generally happens today was a Marine over the IDE team and I'm actually implementing an interface. Do they copy the entire signature, including attribute.

A

For example, if we say maybe now on try take and implement the interface do I get, maybe not as well do as I'm on the hook to like copy and paste it myself.

G

Yeah because if certain sense you have to Riano tape, I think we said, then the IDE should definitely be propagating those. Yes.

J

Cookies I believe I've ever I really nicely I need it. Bill makes an interface that add an attribute on it or, if I've ever used an interfaces, remember how that should be I.

G

Don't think it I'm pretty sure it doesn't propagate attributes by default, because I've used that with common drop before and it definitely does to propagate those I mean the compartment.

D

L

Should probably special case, he said yeah yeah.

G

I think these are the agent accompany yeah things, semantically relevant to the compiler should be propagated if they're not transitive, heavily used, yeah.

F

When you don't have to propagating the compiler, you can search for the attributes from his.

G

J

But for the notable feature are we know, the idea is accented. You have to propagate them because you could have an attribute, say 1100 on the one we.

H

J

There should be a way of expressing dollar that you should be well.

A

We talked about this when we looked at the a transit it's impossible to design that in such a way because it because inheritance doesn't work in that way because imagine, for example, you have like three arguments and you want to change the behavior of one of them like how do we express that point? We have to copy everything down, but now now, if you need to copy everything down, what does omission know mean?

A

Do you inherit for the parameter from the previous one, or do you just this is not being there in our statement of is not being there yeah? It's not it's not something that you can easily express, I, think in general, like I'm, ok with them having to be copy and paste it down. It's just thinking my gosh. It.

F

Was simple basically, like you, Margy attribute the same way as you say: ok, this can apply some methods. So just one more, you say yes,.

A

F

Very sorry, for you four times.

A

It doesn't you can't express that well,.

G

In the other cases, if your propagating and then your reference assembly changes and they decided to change something upstream, then like you now get it you, you may get a silent change in behavior or you may get a warning depending on what exactly changed. You probably want to be number five most of the time. This sounds like a complicated.

G

A

And you certainly like generics in the Xavier I list of a numerator of key value pair of long comity, for it.

I

It was snowing, I guess.

A

That makes sense, have you reviewed, like you know, because now.

C

We're not doing it for this release.

A

And then promises liquor. Let me do that so.

A

I think the rules for link is every time it's a generic parameter of your two shots.

G

We need more than one Bob yeah, we'll live stream it and then we'll just end up like passed out on, came up to me, like I, really.

F

L

That, indeed, would be stream for two days.

A

We're setting this by the way, that's according to twitch, at least against their guidelines. You can't actually stream you're drinking yeah, but we stream to YouTube.

A

It looks reasonable.

A

Anybody else any feedback, otherwise I call that interview.

A

So that means they can't rewind looks good, as is oh, we just need.

L

To pick the attributes yeah the cabinet's across the board right like there, we haven't looked at attributes. Oh no! No, there was a kind of I know what I need the API is that return int way to change.

A

It, and maybe no so that's true. What I think is that I don't care what those, because they have to be reviewed, attributes there at all. So we have to look at the whole thing anyways. Well, that's.

A

Fine all right, so then let me get this over well. That is very big.

A

L

Oh answer we did leave me two buffers yet no right, no superb offers is very simple. You just you just customization like it. He didn't have any.

N

Question what's also very short, so that's fine, alright, so buffer should be.

N

A

Q

What are you doing? Are you building something please treat me like he's emulating your.

G

Q

A

Mine does all the work.

A

Alright, it seems.

G

The behavior, when, like it don't we have some cases where rent fails? Do we just throw in that.

B

Race, yeah, there's and return in every implementation requires the encoder a terminal, but.

G

Not necessarily of minimum length.

B

Right correct: you can return any charger, I mean.

C

It's it's fine for return to throw if you give it an array that it didn't give you yes.

B

Mm-Hmm at the at the moment, I don't think we have any implementations that do that, but we were considering putting a diagnostic mode in the runtime, where the array pool would throw if you double returned or return, an array that didn't belong to it or so on. Do.

C

Actually, if you, if you give it an array of length like four I, think we'll throw because into the share book, is there's no bucket that will fit into nice right. If you give it a read, couldn't.

E

Have produced right yeah, but it doesn't. You know if you return one of the right link that came from different coolness and sir look.

B

At that you're right, okay,.

B

You'rea I can't figure out what bucket the array goes into or throws okay I somehow miss that behavior nice.

A

I, don't look like I'm doing something, but I'm actually doing something. I can I can see. If I looks at me, it's like what's going on, what's going on.

A

Yeah I just secretly playing video games. That's why his laptop was going crazy because we're both playing a game right.

G

We both allow and return, though, for these rather than empty string or what suppress message or attribute for both of them. We.

B

Just returned whatever you passed me because structure, okay, yeah yeah, so the code analysis, one is just you're right, simple worth watching.

E

Right but our previous rule, our usual rule with the attributes, is if we don't think it makes any sense for you've declared it with the null literal. Then we say it's non null, even if it would work yeah we're generating so.

C

For generating code attribute, I looked through a bunch of uses and I found a bunch. More version is null so that one I think made a lot of sense to be string. Question mark I couldn't find anywhere tool was null but I sort of imagined places where someone might want to slap, generate a code onto it and not be specific about what created it. So, what.

G

Would empty string not be better in that case, to encourage that instead? Well.

C

It's a question: this has been out here for 20 years, so it's it's a question of not necessarily what we want, but what have people done and I don't know? I I only looked at our own code, so I in our own code, I found cases where version was no I didn't find any our own code where tool is known, but that doesn't mean that doesn't exist. Yeah.

G

I just wanted to make sure that we were decided what we were deciding wine. It sounds like this is similar to to string mm-hmm, I, guess. One question.

J

Then is: do we want to start with the nominal and make it no later or do we want to start with our tool yeah or do we want to start with the null and they did not know we find out.

G

In in five yeah, it might be easier to make it not Nolan than relax. It.

E

I mean that we would be, you would get tooling tell you that you can always depend on tool being not null, but if people in the wild are generating it with null, then that sounds like we've lied so saying it could be all when we don't know of a case where it would be is probably better. Yeah.

C

I mean the relaxing thing is an issue, because we have both in position and out position here that need to match.

A

Yeah either one you have, the breaking change might as well start doing. These things might be.

E

Good document we could think the property, the out position, say it's nullable and make the parameter say that it's non knowable, but that seems artificial. You know and I think that most people who are using generated crowd attribute are just you know, generating their generated code attribute, so they probably wouldn't even notice the decoration when they reach.

A

Well, anything else on the screen already takes offense to justification message: IDs go target.

A

N

It's all reasonable to me.

B

Don't don't properties like that have to be knowable string anyway, because they're initialized to default of T, like isn't that not up for debate, but a last four on the screen? Yeah.

C

The last four windows.

B

C

Are almost those are very frequently no yeah.

A

I mean they don't have to be, I mean dick. The constructor can decide to set them rather than want mine I mean it can just be empty string, and we have done this in other places. Oh I think for attributes. It doesn't matter with this degree I, because yeah, okay,.

B

I didn't know if we were reconsidering those design disguises for this.

B

A

Know think there's a way of doing okay, so people right then I know this one whenever this month and then he throw up the tracing one.

E

Maybe but display unit is Napoleon.

A

Why don't you say that somebody else recently said that oh no I know it was it was you.

C

That one just changed right and that just changed to be string instead of string question mark I.

A

Don't think we made a decision one way or the other I think I, don't know what that I remember what they said: I needed to think that they said it. It's not now I think.

E

They said it was not no in the in this week's review. Yeah.

G

I think I think we agreed. We would change it to be empty string.

F

So that would mean.

F

G

I made the joke: we'd have to look over them, but either way it's think.

C

I think that's already up for PR there's a PR pretty sure that I reviewed that change. That is.

B

So, looking through the code, I don't see anything the fourth bids, a null value being added to metadata.

B

Maybe it's not the intent that people do that, but I don't see anything that explicitly forbids Oh or he or value or both for value. Specifically, he is going to throw if you pass a knoll, because under the covers against attitude.

H

Olympic code, which you know.

B

I'm, looking at.

G

You want to know.

B

Me usage over and.

G

I think it makes sense in some cases for metadata to be no, because someone might want to differentiate between no value is provided or values.

B

Actually, provided null is treated the same as empty string when you add it to the metadata.

I

B

I don't know if there was a mistake that it's treated like that, it's just that's the implementation. I think that is generally how we do key.

A

Value pairs I think he is almost never allowed to be now like value, is almost always a lot to be no okay.

A

That seems consistent or will be.

C

Where's the metadata used it.

B

Looks like so, there is a get metadata string method inside of diagnostic counter.

B

It looks like when it's being written to the event source. There is a metadata property on the counter, payload object and that property is just a string and it gets the the metadata dictionary gets serialized. As for every key value, two people get serialized as key colon value, comma and Nolan. Empty values are just empty string normalized, so it becomes a bunch of a colon B, comma C, colon D, comma dadada, and that gets written out somewhere. I, say.

C

Another follow-up from this meeting is to fix this implementation to not allocate so much yeah.

E

Yeah I think you've, given the key would throw it's correct to be not null value being null like it. It functions if it's null, so maybe that one should be unknowable. Although.

C

It would probably require a functional change because otherwise it's gonna show up as empty in my look well I guess it doesn't maybe the same as empty I, don't say: I'd be. Where did you see key colon comma? But that's.

E

Already, what that's? What knowing you're both gonna do right, since it's null works and has a behavior that you can't distinguish from the next best thing, which is the empty string, but I think saying that they're, both not null with just a few people if they felt that they wanted to add null they grant that they wouldn't be able to get it back from.

E

Hey I go away. Yeah elavil is more honest. Yeah.

B

I, don't I don't see a way in the code to get back. The individual key value strings that were passed in the only thing I'm able to see is a way to get the aggregate of all of them together. Already concatenated.

A

A

The message just being empty.

D

D

Oh, it's there.

J

D

J

Really, the only thing that I learned how to do is allowed to have its massive everything.

D

A

I think only thing else happens to be instructor.

A

B

I

Africa, well, it.

B

Is an actual attribute? Okay, you.

F

Could you check the event keywords? Is it across Australia so.

J

It actually doesn't have to be right. This isn't enough, so you think they're. Lastly, and you could, but you then couldn't specified it and let it be known seems like a rather pointless a show or.

G

If you're rapping, some existing state and you're taking all the constructor parameters in and then know that, like.

D

This, like you, put it on the class nights weekend up.

G

No so I was saying you could have an attribute that contains a class, but you would require the constructor to take all the parameters to the classes. Constructor. Yes,.

B

That way, you construct it.

I

G

A decimal yeah, what this is it.

B

Looks like it is very, very common.

C

To instantiate this attribute.

B

Without studying the message property very common, it just seems we there message that now isn't.

K

E

We say that it's not knowable and then changed the constructor to set it to the empty string. I, don't think.

F

They don't think it doesn't something yeah.

E

Because because Knoll right now means effectively wasn't set, and so you can tell the difference between, they said it to empty and they didn't set it. And you can't tell if they said it's null, but.

E

Yeah I think it's, but.

I

A

I can't think of a case, but you want to set it to know big things while.

G

We're on that topic, do we have an attribute that says the return? Value of a property will never be null, but the center can take null yeah. So.

B

It looks like, and dull and empty messages are actually treated.

L

Differently or invited callers out when they're raining down over the other.

B

Okay, I, don't know what to be to them. So what's happening is the the.

E

Event, acronym is being turned into an XML or even.

B

So in yeah, in the event source, the event attribute itself as.

C

Being turned into an XML element of it if and only.

B

If the message property returns non null, the message attribute is written as part of the XML element. Otherwise it's skipped entirely. So changing the behavior of this property to return empty string will actually change the generated XML.

E

And if I recall correctly, the way this bTW works is, if you don't give a message: it'll look up the message by the ID and if you do give one it wins, so we would break diagnostic tracing to the event. One girl.

I

E

Probably back know should we should let it say that.

F

It can be known, come on come on Kevin tax t. Are you on the addiction.

F

Which ones for the red kimono in darks organized in conditioner.

I

I ain't even a dictionary spring to spring question. Yes, drinks, almost in question.

G

Yeah because if we just said we know my lot about, you mean oh yeah,.

B

Well, that can it's double check if reduction, you're looking at the arguments problem.

G

Well, an users can set so since it's not, we don't.

B

In fact, there's even a debug assert and they were saying the property's not long.

B

Maybe they just.

A

Put the question mark at the wrong spot: maybe they might have set it before the closing bracket.

A

Possible, because that makes more sense than having the connection being.

A

Yep, let's just record that as well.

E

There is also code that says if there's a do command somewhere, that if it sees null it, it makes a new dictionary for it. You know something somewhere expects all of the possibility or is just super differently. I think.

B

Isn't that just lazy, instantiation.

E

This is a vent source, do command which takes in the event args. It has a path in the middle that, if it sees arguments command herbs, arguments is null minute instantiation. You know it's lazy, initialization by a different class yeah.

B

Yeah because it has an internal center yeah as I'm looking at counter group encounter group actually debug asserts that the property is not null.

F

But seems like it doesn't have the explicit destructive edge, which means D by default. If you don't do it.

E

To be fair device erting, it's not null if the command is enable. Our update. True trip may be that it knows that those paths will have assigned metadata. I mean.

C

This, this might be a case where we to assert intent but event source not send command, which is public, takes a command arguments. It doesn't do any validation on it and it just passes it all. The way through that's passed into the event command args event convey its constructor and it's soared into the property, know that it could be that we're just you know what are the many cases where we hadn't done public argument validation, even though we expect it to be not null.

C

G

Don't know so Marcus follow-up, yeah.

D

I just recorded that.

E

You yeah I agree with the Christoph's initial assessment that it probably wants to be I dictionary of string to string question marks, but I can't see anything proving one way or the other on that. There aren't a lot of uses and.

M

They all look to be internal right.

C

We should have someone like Bryan Robbins,.

A

Yeah even counter define event, data attribute seems fine.

A

Maybe should be not now the same argument as before, wouldn't be shocked if knowledge until.

F

It's treated differently here, I think the name, but there was a different in current, was no or not. No, it was Papa I think sometimes, as the name is expected to be now and some cases not depending on like that type of thing. I can't remember.

G

Time is teaching on that too, in 30 and 27.

A

Billington second right.

A

What 7 you just mentally the table? No I'm fixing.

I

It fixing the table was half of them.

I

Notes off clothes.

F

The type a destructive arguments.

J

Arguments here, if you thought, would not jump.

A

Ahead of that, right still been.

A

What else do ya.

A

Isn't that also bogus, let me say that parent should never be now.

G

Your compiler will never pass in no, but you can exclusively positive well yeah.

D

You can, but is that whether you got the questions like if it already exception move? Is that basically definitely what.

G

What does the compiler do if it's a string array with like if this was a string, question mark array, that's a params and you pass a null. Does that does it treat it as the as traits is null or does it pass in a array that contains a single null.

G

I, don't remember we're done, no, it's a quite like. So if you, if you have a friend where it's a nullable array and you pass a null, is it going to treat the array is no or no.

J

I think it's something.

J

But whatever we do here does not change from the current right like it's, you might warn about what whatever you don't your fella is more aggressive, so.

G

So so, in that case, if you even want to do explicitly pass null, you would have to do rates : null Oh God. It's.

C

The commentation explicitly allows note, because it delegates from the above constructor to this one with no.

J

But is that passing an array of null or is that pass though it's I know it's passing.

C

It no it's not it. The double check but I'm 99% sure it'll, pass in a dual array. Could.

G

We not just change that to be empty, yeah, I think.

D

A

And that's at least consistent with what we did everywhere else.

E

So anyone could have derived it and been explicitly passing all down already you're.

C

Not suggesting adding us throw you're just suggesting making it not dull. Yes,.

D

Yeah and basically yes, this is a brother so well.

G

For back compact, we could just say if no then treat is empty and we could just encourage people themselves to change it.

F

In what country well.

G

No, we would make we would market non knowable and if someone- and we were to encourage people to change their own implementations to pass it, but for back compat we would say if no treat isn't empty.

G

F

Because people are.

G

Gonna have to be fixing up alive arrays for this, so it's a question of like: do. We encourage them to fix up their code, or do we just want to let it work, as is oh.

C

I just confirmed it, it definitely Pat. If you just say no, it treats that as the array, not as a number theory.

A

That's what I thought I think the parens expansion happens after other things are no longer applicable, and so it reads not the same ways as you would have just passed in a crack. You factory.

A

Generate manifest.

A

Reasonable you.

G

Return null instead of.

D

An empty string if there's no manifesto January, yes, but we know, there's nothing.

A

A

But probably not as simple as that, because almost that never happens when I say that right.

G

Because this is a this is an assembly path to include in the manifest, not necessarily the manifest you're generating, because.

A

It's true, the trade makes sense, I, guess it returns, none of the key doesn't exist or debate happens. You know.

A

I feel like command arguments are yep.

E

Generate a manifest the event source type is abstract or any other reason that it doesn't like it. It returns null to say that the type is not valid.

G

Seems like that probably should have thrown if we were designing it today, but.

O

Since I've asked for.

G

You just like those right event, argument names.

C

Looks like there's an option that there's this event manifest option things think and there's a strict member of that and if it's set to strict in the end up with exceptions and if it's not set that it returns. No.

E

Only we had a guideline that said: don't have a member that decides whether or not you.

Q

A

Q

A

Think you only have this four parameter.

Q

J

Not mom one member, false yeah.

E

Sorry, the flags parameters decide whether or not an amendment through.

A

So it's okay! If I have a property that decides that car.

F

Oh to rights. Take this event for master an honorable stream candy. The generic on states I. Think it's correct by number.

F

So which one is ever right? Basically, the generic versus engineering and I think you.

F

I'm confused, which party tell me around home on the right. Oh.

F

That does look weird I.

F

But it has been correct, but I cannot remember why so.

J

C

Looks weird sorry: oh right.

J

The dimeric right versus the non-generic right, the non-generic rights that names my mobile everyone.

E

Is normal? The non-generic ones definitely do throw in source dot dot net isn't following through on where the generic until the.

L

Generic one I'm looking at it and it falls back into the event info that you pass like Avenue for the name. If it is no.

I

This is actually just in case.

E

Now documented well.

A

O

F

If system can't decide if it liked to sleep seconds,.

B

Though I think what's happened is that we're stuck in a time loop, reviewing knowable over and over and over again for all eternity.

N

All of you have.

A

Sinned in the past, let's your punishment.

B

I watched Groundhog Day for the first time a few weeks ago, seriously seriously well, thank you! It's in it's good, my god,.

K

O

A

B

A

B

I'm stuck here exactly it was, it was actually better than I expected be honest. They didn't have high expectations. Both I shouldn't have gone. First really, I shouldn't have admitted that yeah.

E

It surpassed No, hey.

C

E

Tobacco, but on the whatever things were thinking, the nullable array is params. I can't find any reason that it's not a array of string. Question marks, I, don't see anything, that's walking through a value unsafely wears a those events force constructor, you mean the trades. Yes, I got that this tunnel.

C

I think it's probably a case of it may not be validating it, but what situation would you pass? A null trait I mean.

E

The the problem is that params array is really it's a params string string tuple. So it's an even array where half of them are keys and half of them are values and half their values seem to allow a null. The half that our keys allow null half the time.

E

C

Is the case I think where I would say unless we have an example where were Brian? Robbins tells us that there's actually a case where you would have a null value on purpose that we start with non nullable and back off to null. If we actually find this problem.

A

Api and then show the sample code. I think I gave I'm half way in because it was a bit weird in the in the way the trades were posited because yeah they were basically key radio chemokine. What's a bit, it was a bit odd, so that might not be actually an encoding that actually represents intent to goddess over there. No.

E

Yeah I'm, okay with saying it's non null Abul and then if people complain that they passed no all the time and it totally works indoors and we can eliminate question mark something.

A

Tells me that's not the biggest problem with this API I.

N

Don't know why I would say that on.

I

F

The rest looks pretty consistent. The right amount of the Ark's object right there, possibly.

A

The object might.

F

Be malleable, yeah, that's not sure.

A

It seems a bit with me alone, not strings, we don't know no okay, it.

C

Translates no string to empty string; okay, silly.

B

Question pointers are still allowed to be nolde, even with notable annotations.

F

J

You saying that the.

F

Object should be in the level because we translate this into the no.

C

I'm, saying string should be nullable I think it's correct that the object is not no okay,.

F

It's consistent out every.

L

Event, source target rate.

A

Would you go out to answer doctor tree? Let's even know, do you think that's weird to have like the string now the bow, but then the object, not knowable.

A

Okay, let's say I call the next API that they're passing three strings now I'm passing the fourth string and suddenly I came along my positive manner.

C

A

C

Looking for I'm looking for the.

F

A

Doing this man kinda over that it takes four arguments.

A

F

Hold the medic number is 16 to anyone like this action. I think action is in front here. 16 here.

A

Well, they are basically arguments to the action right because that's what the variables are I mean.

P

Yeah but like you needed, there's no params generic, no.

A

We shouldn't have it varied. Attempters are not making a lot better. Would you go off to get right? Get it right? I can find my mouse again.

L

P

L

The key is not knowable, but on implementation there is nothing that prevents the key from the English you're sure about my.

J

Now it's an exclusive mal'chik yeah, um but.

L

It is doing a comparison of the traits traits on index. I equals equals key personal issues, but the traits are marked is, if you have to know yes,.

J

It's a picture just safe guarding. Instead of flowing it just like I, yeah, I guess the thing is it yeah.

A

I'm clearly leggy to write if x equals my return. Now you bail, you just chose not to throw for that case right. I will.

J

Never return a useful result.

N

A

Given that it doesn't actually use the key to index in our cases, the use of the big key compen are all right. So then, back to the pair of snakes, the Stevens clicking around something or oh yeah,.

C

Sorry I, it doesn't like null objects. The oh yeah I was about to say it explicitly external.

E

Object, you have said it returns false.

E

This is so weird it'll, be art, just not know it doesn't match the parameter type or it's null, and it couldn't have been that parameter.

C

E

C

But when it gets down to processing the event payload and it doesn't event, payload and X does not equal, no stuff else. Return code equals null input return. False I only made it to log of it.

C

I mean double-check me: Jeremy yeah keep going, but you I'm looking.

A

A

All right, I just took a note that it's just inconsistent and then we can decide to fix it either way and putting on fixing, but, as I said, not the biggest pharmacy. Yeah events are, that should be a GUI localizing, localization resources and name.

K

Miss P type this drink yeah, because it's an attribute.

F

I guess it's true: you can actually yeah I can't specify get the good absolutely. Are you gonna pay together.

A

That is actually fear.

B

You so offense first created even orbs. Eventsource has a good Ando, cetera.

B

B

It seemed suspicious doesn't.

I

It but the art it's the thing we looked at earlier, durable, it's the they basically.

A

Don't expose the constructor that takes them.

A

Which I give you is fishy.

A

We need to see a doctor is the screen flickering outside of just this thing at the bottom? These things.

J

Are not usually exclusive have.

G

You tried this connecting.

M

There's no flicker on the stream, so it must be your emo good. Just today in false dichotomies.

A

I will certainly take more shots after lunch.

A

Is then written, even our exhibit? Also this consistent of a earlier event named message. We said it's treated differently for now.

A

Paedo is read-only collection of inaudible object and payload itself give me now. It seems unfortunate.

I

The names can't be, no, the collection can be yes,.

A

Right yeah again, this is very unfortunate. There might be four perfect.

A

You should be able to sing.

A

O

C

Oh Jeremy, you might be right in some situations. On the eventsource thing it looks like depending on how things are configured sometimes nulls are allowed, and sometimes they aren't.

A

So we are basically a partially consistent.

C

Yeah we're good right.

E

So it should be object. Question mark question. Mark is the second one means we're not sure.

C

Yeah I think this is a case. Let's start with.

A

C

Mean it's weird to pass in bells here. So let's leave it off and then, if it's a problem we can add it back all.

A

Right so the other ones are things we are fine with the bunks, don't being no I. Suppose I, don't like those bunks in general,.

G

A

You said it was a view, so the listen.

G

Yeah and I've gave feedback that I, don't like that word. Summing doubles.

F

G

A rounding error.

D

A

What I, like that? Alright, let me close this what's happening here is that I can instantly have.

D

Fractions, we can write.

A

This, you probably should just unplug before you close API. Oh no, this is I, don't think yeah. It might actually be one into the bigger view as in trouble, but I don't know which one oh well.

G

I, don't think it's just gathering you, because your time is messing up. Yeah I think.

A

That's the overlap, that's the overlay because it's like I, don't know what do I know. Nothing apparently.

A

They totally help ya close-up of the APA degrees. No I can't I get a spin, yes to open. Oh I'm, not doing that. Alright. So that's just.

G

Looking for whichever one zoomed it like 140 percent, it looks like it has four added in 225 Oh.

A

Doesn't seem to flick on the screen, you know that's true. Maybe.

Q

It's too fast: it's the projector, probably of the string.

A

All right reflection amid we have ten minutes left, let's use the time and at least get something done, customer to you builder,.

G

Why can't you have.

B

No arms in there object probably should be allowable you. You can have no arms, but you have to pass them. You either.

G

Have to call to the object overload that doesn't.

B

Take one I'm, sorry, no so right for the other ones. You have to pass the nominal.

M

If you call those particular words, if it.

B

What's actually.

M

In the Rosenbergs isn't awesome yeah but can't be arguments themselves banal.

D

And same for the property, various others yeah, no, because I think the the arcs are.

D

I see what you're saying you're.

E

Good pass null that would be a null value in the constructor earth array right.

M

Time saying this should be object, question your question, mark array and you actually do if constructor.

L

R is equals null and many forum types of I is value type through our dimensional exception, I mean.

G

Right now, but that.

L

G

Type, if it's a reference type, it's valid to be. No, that's that's. You asked you know in Korea,.

J

Amazing, it's outside.

G

The scope or they're, not oh yeah, make sense yeah, so I think several of these. You should be of DIC posteriori, all right right, yeah at least for the ones that take values, because you you have no clue whether or not the thing allows null generic and then presumably the thing that the constructor you're calling will throw it. The inputs Nolan doesn't allow yeah well, actually it won't because it's an attribute- and we said those don't throw so so.

E

You can actually a bug if it throws if it gets a null value in a value type, because that means it should just be knowable them like because know what Bowl boxes is know.

E

G

She's never coming. You can't have nullable in a constructor for because that's not expressible as a constant I can't.

E

Take I can't have a okay's good custom attributes right.

A

Let's try it I mean you can't pause now to a constructor. You.

G

Not for nullable of X, because that's all I get in question mark yeah.

B

Like if you had an attribute that took anything, that's.

K

B

Testing it real festive verify. Why not.

F

I'm going to come back to him correct.

B

Tried making an attribute with a question mark parameter and got a compiler yeah.

A

B

A

Minutes left I mean I'm, not sure it's actually work. Why doing the rest? Because it probably might as well just.

F

Yeah yeah, all of those are its trucks right, mostly example of a builder yeah.

E

Yeah, so we I mean as long as if we believe this one has been done already, then we already have to feed back that custom, attribute builders, property values and constructor args and presumably whatever's after field info array named fields. Theoretically, all of those should accept null inputs because I guess it says there is some change here. So maybe that was just missed doesn't to make sure we didn't have a that. We were looking at a thing that actually hadn't been crossed.

E

So there's already cleanup, but we can start it started this when I get next thing.

M

Yeah, oh, it's a pretty small when we might be able to finish it in the next five minutes. Now.

A

A

Then keep going because I need to ride allmovie the same. Oh, yes,.

D

We rolled out we've already done seen. You see some reflection, primitives.

F

A

It can't be naughty because it's a switch right. You have to find at least one light bulb, which one the one who takes it around labels.

G

Then we can say, don't worry anytime.

I

G

You scroll that again.

F

The operators from the label rubbish, I, know caduceus yeah.

G

And parameter name- and you know I'm guessing that's used for positional parameters.

D

Let you build it and then.

G

G

Argument we allowed all on this rather than require you to call the one that doesn't take like we do in the other ones.

G

So so, in the custom attribute, we said you didn't allow no on the bike parameter names or on the parameter, names and stuff, because we required you to call the constructor that didn't have that parameter. But for this one it looks like we were allowing me to pass a null and we just treat it as the same as the add argument, one that doesn't, it seems like it would be good for a consistent for consistency, sake to update the former to allow passing in null potentially and then just forwarding it down.

G

Which one would there be like it would be like name fields would be, would allow a nullable array, and then custom attribute builder would forward to the next one. Presumably, it's just an inconsistency, because the guys there.

G

G

G

G

There, because all we do is we, we just invoke a common internal constructor and explicitly pass it and do it the arrays, even rather than a radar empty.

A

A

A

We sing all right anything for this or should be diseases. This no.

G

I think I think that's consistent with everything.

G

D

L

Did we settle with something for tomorrow? Probably should is that week.