Why null safety? | Session

[@jdheeter]

This man is great at explaining things

[@thebirdhasbeencharged]

You should read his books (Crafting Interpreters and Game Programming Patterns), walking wizard!

[@philosophia5577]

I felt the same entire time. This video gave me a lot of topics to explore after which I will rewatch this video for greater understanding.

[@StanislausMadueke]

This is definitely my current favourite IO talk - just the right level of detail for such a complex topic. Great job, Bob! Hope to see more from you in future. ♥️ Dart and Flutter!

[@awsumgeorge]

+1; The speaker's profile badge is quite misleading, though. Bob does not look anything like that picture nowadays, and the chihuahua passed away since the picture was taken. (Check out Bob's books, btw. Good stuff; approachable and informative.)

[@nicolalanzoni674]

@@awsumgeorge Hey Jiri, what's the name of Bob's are you referring to? I'd like to take a look. Thanks

[@awsumgeorge]

@@nicolalanzoni674 They are "Game Programming Patterns" and "Crafting Interpreters". Both available to read for free at the book's websites.

[@huthaifa5]

When I listen to Bob Nystrom talk about Dart and Null Safety, it feels like listening to poetry. Not even sorry for how geeky that sounds. Amazing work guys, always happy for the constant improvements and changes you keep providing.

[@SundiMyint]

I have seriously never consumed more articulate code content on the internet. Thank you all for your hard work and putting time into making this content for us!

[@pauek]

I love that you decided to publicly talk about the complex decisions that went into implementing null safety, and not water it down. Thanks so much!! This can only strengthen our confidence in and attachment to Dart and Flutter.

[@kamil_supabase_enjoyer]

THANK YOU FOR NULL SAFETY. BEST FEATURE EVER ❤

[@jainam9805]

i don't comment publicly often but damn this guy busted my brain with knowledge of language designing! Please start your own channel and disperse knowledge of dart

[@LohenYumnam]

Coming from Swift .. I love null safety.. awesome job guys ❤️❤️

[@krishnateja4688]

really ? the persons who came from swift won't like this cause this doesn't has if let or guard, which is crucial for type promotion.

[@LohenYumnam]

​@@krishnateja4688 ya that part I miss a lot. I miss the power of enum, in swift too. Dart is not perfect but they are trying. It’s funny that if (x != null ) is the alternative of guard let or if let

[@波波-j1i]

@@krishnateja4688 Came from swift too. its just a litter bit more code . i will take it.

[@azrulihsan4085]

Such a relief with null-safety features in dart. Been migrating my old projects and it felt like a heavy burden lifted from my head. Good job flutter team!

[@huxpresso]

I don't use Dart but I studied PL in school so I love the balance between being pedantic and being pragmatic during this talk ❤️ Definitely the best programming talk this IO so far!

[@Neoclassicalmaese]

This man claims in his books Crafting Interpreters that language designers are no dark arcane wizards. But he cannot fool me, is IS a dark arcane wizard. Thank you Bob for sharing your knowledge with the world!

[@samgamer3530]

Terrific presentation -- Bob, you are killing it

[@roger58469]

This was really great to watch, an excellent explanation. Thank you very much for the video and kudos to Bob Nystrom!

[@dovas90]

Great description and explanation! Thanks for the help. I love your team!

[@MichaelDuarte]

This is awesome, thanks for the super easy to understand explanation of how this works and most importantly, why!

[@dantedt3931]

Great explanation. Flutter is the future!

[@Yous0147]

Amazing video, great overview and very insightful discussion. Really enjoyed every minute.

[@osamaali6603]

Wow! This was an amazing talk. Poetic!

[@nordern1]

TIL: We use C because Pascal had static array sizes :P

[@jrheisler]

Flutter Web app, just migrated to null safety, it is noticeably faster, and the migration tool!!! Well done!

[@peterhuijsen]

Really well explained! Loved the talk.

[@muneebmukhthar4880]

Best I/O talk !

[@SaiyanJin85]

That was great! It makes me think about my code in other languages.

[@dc5]

What a great talk! Thank you, Bob! About fields and top-level having to use the bang... I still find it a little odd and not sure if it's good practice or not to do it that way. For example, that screen at 14:38 looks scary ... if (_positional != null) rules.add(_positional!); I have many of those around and just feels odd. So I wanted to know your opinion on whether that's ok or if there is a better, recommended way of handling those?

[@pierre-louisguidez2040]

This is expected for fields. The explanation and an alternative to using ! (copying to a local variable) are explained at dart.dev/null-safety/understanding-null-safety#working-with-nullable-fields

[@dc5]

@@pierre-louisguidez2040 thank you, that's what I've been doing... A mix of bangs and local variables.. just wanted to confirm it was good practice.. thank you!

[@SethuSenthil]

I always wondered how the Dart engine checks null, this is crazy

[@nicoeg]

Such a good explanation and really good talk!

[@baraaaljabban9058]

I read a lot of comments say : great talk (and really it is), but I don't know why I fell it's too heavy or it's so hard for me to understand it easily 😂 I'll get back to it agin to understand more. Anyway thank you for the explanation ❤️

[@bibitepower]

Null Safety is awesome, you did a great job! 💪 I think we're all waiting for type unions and data class 😉

[@Kitulous]

7:50 coudn't the outside code update the list? like in the first isNotEmpty call it had no elements, therefore border didn't get initialized, then some other code in between the two ifs added an element in there, and the second isNotEmpty succeeded, and we got an uninitialized border variable. List can be mutable, it's not some sort of read-only list.

[@agung_laksana]

Please provide optional casting ( as? ) like in Swift and Kotlin

[@_chappie_]

Interesting. I've always thought the idea was to eliminate null values all together, unless absolutely necessary. Thanks for the insight.

[@sohelakhtar8044]

Great talk❤️🇳🇵

[@Pablo_IF]

Great video!! Many thanks!!

[@ruynobrega6918]

One of the things that made me use less python was the dynamic type check/null check. It REALLY slows down apps. Typed languages are the best to read and write, and null safety improves both readability and performance. To be honest, I don't think there is any drawback here at all.

[@CleisonArenhart]

It can be pretty painful migrate an old codebase to null-safety. I ran "dart migrate" and i've noticed that our code is not prepared for that. A lot of usages of maps as indexes which needs "!" operator, a lot of variables that needs to be late and the migration didn't recognize it, so made it as nullable ("?" operator). Now I'm looking for 466 files to check which one is right and which one is not. Basically, I'm re-doing everything. At least, de migration marked-up which file I have to look.

[@krokenstiv8777]

Supporting both dynamic and static typing is a very smart decision. Also I like that I can use Future as a coroutine or as a promise depending on the problem. But nullsafety is not important for me.

[@kousheralam]

Nicely explain, love it 🤩

[@tananga1523]

Love this videos ! Can you guys add support for Dart in Cloud Functions ? Is a shame to use node or python. That will be legendary !!!

[@sthiag0]

Wow. What a great great talk.

[@Randomdude-i8x]

Instead of a null error I just get unexpected behavior that takes a while to debug. If i get a nullpointer I immediately know what is wrong and where to fix it. Maybe I need to get used to it?

[@amitm29]

Awesome talk!

[@siyabon_ga]

Bob needs to explain all flutter/dart confusion related topics coz green light all of a sudden on my side.

[@aminelahrim8142]

Thank you for the informations I like null safety

[@danielbarnett5764]

Had to like this video. :-) Im new to Flutter/ Dart but is there an "undefined" value rather than null. I.e. not set vs actually null. Detecting something never set is a useful conditional test. Seems relevant to the example. Cheers great vid

[@mobileappsdevware264]

Hi man, i start to learn dart and flutter, i wonder why object in in flutter can't be mirrored or reflected, i need to list an object properties , in other words i need to make some thing like GSON Lib (android) and JsonDecoder(iOS). can we?!

[@adamcierniak3902]

How to disasembly flutter program ? I mean how to extract lower levels of abstractions from dart to assembler?

[@xXxBladeStormxXx]

But what about null safety in Lox, Bob?

[@m00ni]

:D

[@idlevandal69]

Great job!!!!!

[@richardjay1791]

Sweet. Thanks

[@demondragon6198]

it's informative !!

[@evandrojunior7628]

Amazing!

[@obengkuning3260]

Why?

[@akhileshsuvarna8830]

💙 from INDIA

[@Shakl-e]

I am not afraid of null anymore

[@danvilela]

300 IQ

[@huthaifa5]

IQ overflow*.

[@MyrKnof]

contrary to everyone else, I hate this so much. As someone who just got told to upgrade a 5 year old app its all just: late late late late late !!!!!!!!!!!!!!!!!!!!! ??????????????????? and hope it works afterwards. I got no idea what I'm doing or how to fix anything. Perhaps im just too dumb and lazy to be a programmer. Everything worked fine before.

[@justchecking2470]

and then suddenly all tutorials from old versions crashed

[@mortysmith666]

After migrating to null safety, my app size became doubled

[@francisgeorge7639]

Good presentation. But Google still need to be employing professional documentation writers and not engineers.

[@m00ni]

We do have two very excellent tech writers on the team. But we hear from many users that they appreciate learning directly from the engineers who work on parts of the system. (Also, I am an author too, so I guess technically I fit your criteria.)

[@gokhangorali5385]

Electrons? detected :))

[@francisgeorge7639]

Delphi solved the Pascal string problem. It also had almost instant compile. And Oh my gosh it was so much simpler than Flutter. With Flutter we're almost back to 90% UI coding 10% business logic, which Delphi switched. Delphi died because Microsoft stole their lead developer, who went on to design c# and Typescript.

[@coom07]

Bruh. Can u keep talking in every google IO