Shadowing Practice: Mastering iOS Development: Mock Interview with Ramiro Neto - Learn English Speaking with Video

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Right.

So thank you for joining, Romira.

And let's just quickly go through some agenda for our smoke interview.

So firstly, we'll just talk about, you know, some do some introduction, then going to be two sections.

First one, more like soft sections of skill, your behavior driven section in a way.

And then the technical part, the technical part, we will split for two parts.

It's one pure task, pure questions, both, you know, classical Swift, iOS, SDKs, questions, and the second part,

more like example testing, let's say.

So I will drop you some piece of quotes, and then we'll just talk about it.

No life -building, no kind of algorithms thingy, just let's say...

Discussion.

Yeah, just discussion, basically, like a classic thing, nothing more.

So that's it.

Let's start.

Let's see how it's going to go.

Yeah, let's start from the introduction.

Let me start it.

So my name is Ildar.

I'm now located in Sweden.

I'm working in the H &M as a lead engineer.

And I really like to drive such sections like mock interviews or in general interviews.

So always nice to see and talk with the new people and see how we can be used to support each other.

Yes, what about you, Amir?

Yeah, thank you for the opportunity.

So I am Amir, I'm from Fortaleza, Brazil.

I have been working with software development since 2012.

I started as Android, but after that, I did the Apple Develop Academy course.

And after the course, I worked with other technologists like PHP,

Muscle, React .js, and others but I got back to focus on iOS in 2017.

And yeah, I have worked with several projects and companies and like telecommunication companies,

banking projects, and also digital wallets, e -commerce.

Yeah, that's it.

Yeah, really, really nice experience, I would say.

You know, especially this kind of different experience from different areas probably gives you, you know, a sense of understanding how things work you know,

I draw it or I end up in a way.

So that's really nice, especially for, you know, agile teams when you need to be agile, you know, I guess.

Cool, cool.

Right.

Let's just then jump to the first part.

So behavior driven questions to warm up in a way.

And yeah, just to start all this.

Yeah.

Since you have some experience, I've seen that you have more than five years experience in the development right

or in general in development you probably had situations where you need to review code of your teammates um

so really interesting to understand how you're doing it

so for example um you have a team of three four people

and you need to review each other right

and you need to review someone's code

so how do you do it here you you have a rule

that uh a pure pr to be approved needed at least two likes.

The team needs approved at least for two two person to be approved.

Yeah, I have to work.

Okay, do you think two person is enough for approving PR?

What exactly?

Two person, not one or not three?

It depends because our team, it's not a big team, you know?

So as you have less numbers from people, I think it's okay in your case.

But of course, if you have a bigger team, it would be better and have more likes.

Okay.

Yeah, yeah.

Fair enough.

And for review, when you're reviewing some word code, you know, usually people trying to see for something specific

or have some we have some pattern to you know scheme the code

and catch some some of the things can you maybe tell

what usually is catching your eyes on the it's maybe syntaxes errors

or some kind of boss symbols in a way yeah here you have a some a partner for CodeStyle.

So we see it in the PR as guardlets, as possible iflets, trolls, or yeah, some things like that.

Camel case, uppercase too.

And also we try to see if the developer is following the clean architecture that it's necessary for the, the improvements.

So that's it what I do.

Interesting.

Right.

And then when you're working in the team, you usually have a designer and some backend developers and you need to,

let's say you need to work on some feature where all these parts involved,

what would you say is best way for communication about new feature

or how to be sure

that some specific feature is uh you know in the best shape

when you're finishing it or you when you you know

when you finish the work how to be sure

that uh all the parts in in the place

when you work yeah it's a it's a it's a very good question it's a complex one you know yeah

and i think uh the design maybe it's the the first parts of the idea.

We, as a mobile developer, works in all the parts from the idea.

And so when the design presents the idea for us,

it would be nice to see if you have some technical implications from the implementations.

And after that, when you are implementing the the the feature

that is approved for design and for us we need to see if the the the backend it's

it's everything all right or what you will need implementing the backends or to to

to develop it in the mobile yeah yeah okay and let's say design is finished for starting the work,

but back -end not.

Is there any way you can still start working or you will wait for back and fully finish the work?

No, honestly, we can start to work and create interviews at least.

But of course, it depends from the case.

But as I assume that you have a BFA, we can close a contract,

you know, like I agree and agree be agreeing it in a contact contact contact sorry

and yeah it started develops the view

and maybe with uh uh uh creating a block or something like

that right right yeah sounds sounds great

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and let's say the final question for this you know the classic situation

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when you have some technical depth as unit tests or some refactoring

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and you also have your features that needs to be delivered.

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How do you find a balance in that?

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Or how do you maybe as a senior developer can recommend to your management or team how to resolve it?

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So you're not stuck fully in the back block with all this technical depth, but also you're delivering the features.

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Do you have any tips, tricks, how you find the balance between technical depth and actual features.

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Can you repeat the first synthesis, please?

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How do you find the balance between the technical depth?

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So basically tests or refactorings and the features that you need to deliver because, you know, usually management pushing for features, right?

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Or business pushing for new features to release.

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But you know that you need to cover something with a unit test or refactor something because in the future, there is some consequences for that.

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So how do you find this balance?

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How do you kind of sell it?

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Honestly, I think that's for a mature team.

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We need to spend at least like time to cover some tests and fix some bugs.

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And improve also our code bases.

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I think I find the balance for it.

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Like I haven't taken priorizations from the features between the others,

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things that you need to improve the codes, like the tests and the others factors that you need to do, as I said.

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Right.

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So I think it would be a priorization between these ones.

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Yes.

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Yes.

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All right.

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So I guess we can wrap up with these behavior questions and then smoothly go to technical part,

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but I'll just give you some feedback after each section.

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So not to forget about the things.

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This section, I would say that all gifts for behavior questions, your answer is solid about how you behave, how you do, especially part about.

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you know, how do you find the balance in the technical part between these features and technical depth,

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because you always need, you have such experience.

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I mean, this is something where you can recognize that person has some experience to actually work on technical depth, not just work purely on the features,

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because you really need to think about it and you really need to

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reserve some time in your daily work or your sprint or whatever you call it for specifically for technical depth.

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You could be a bit maybe descriptive in a way for how exactly you can do this.

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Let's say that you can reserve 20 % of sprint

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or technical depth or have some iterations and indication in the team that that if we will not do this,

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then there is a consequence for businesses to sell it in a way for the team and present it.

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It's not just some updated work or not needed work, but something really important, not only for us as the developers, but first of all, to the business.

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Yes.

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Right.

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Let's jump to the technical part.

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Yeah.

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Let's just start from the, some, you know, easy, easy ongoing questions.

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So where in the Swift, we have the structures and classes.

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Can you explain to me what is the differences between these two?

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Yeah.

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The main difference is because the struct, it's a value type and class, it's a heifer type.

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So it's created a heifer in the memory.

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So it's the main difference.

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All right.

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Maybe, can we, for example, inherit structure from another structure?

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And no, you can't, I think.

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Can we inherit classes?

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Because it's like a structure.

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It's a copy one from the object.

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So yeah, it's immutable.

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Yeah, right.

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Can we inherit classes?

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Yeah.

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Yes.

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Can we inherit, let's say, two classes?

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So one, you know, we have class A and then we inherit class B, class C.

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Yeah, you can.

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Okay.

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So how we can do this? so i just decided to describe

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or you meant something else yeah you can create like a final class

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and like in here to other like a network uh protocol class

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and they are that would be inherit from a protocol

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and you have a network service class and a mock services networks okay

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so so you meant protocols

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but i mean can you inherit you know classes just after you know comma class you have class a

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and then you have just a pure class b

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and then comma class c comma class d can you do this yeah you you can do it like

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and create like an um let's see um a knowledge case

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and y view controller

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that would inherit some some functions to to analysis to to send to the crash leads

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or send to the Firebase analytics some functions to analytics.

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Or you can create a view that would have a background like rounded and grey.

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I don't know, and every view that your design systems would be narrated from this one.

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It can be created in the final class.

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And yeah, like a super class.

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Got it, got it.

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All right, let's move further a little bit.

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So in the Swift, we have different types, right?

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So, and we have so -called primitive types that usually variables.

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and we have reference types that usually is something bigger than just pure variables.

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Can you tell me what is in this system?

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What is closures?

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Are they reference types or are they value types?

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Yeah, honestly, no. I don't know about it.

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Not sure.

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Closures.

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You know closures, right?

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Yeah, I know closures.

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I'm not sure where to.

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Okay, no problem, no problem.

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Right, and then maybe if we go a step further, let's maybe speak about the memory management.

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So we have a memory management.

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Can you explain how it works in the iOS?

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Yeah, we have a GCG on iOS and it works with a lot of threads.

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Yeah, we have ARC 2 that's that have the memory management for count heiferis.

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And yeah, it's the automatically way that Swift works with memory management.

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Right, right.

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And for ARC, you have, you know, so can you maybe explain in the details a bit how ARC works for us?

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Yeah.

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How that works?

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Every time that you create a new object, it counts one reference from this object, this one.

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When the object would be deallocated, they decrease this reference from the memory management.

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But of course, if you create some strong references, it could not decrease it and maybe crash the app,

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create a memory leak.

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Do you know how it's called this kind of bad situation when you have one strong reference to another strong reference?

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Two classes have strong references to each other.

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Do you know how this situation is called?

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How this situation is called?

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Yeah, I know the XETLIN name, but I forget.

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Sorry.

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No, no, it's not a problem.

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It's called Retain Cycle, right?

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Retain Cycle, yes.

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Because you can't retain actually.

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Yeah, yeah.

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So I thought how to resolve it, do you know how to resolve such situations?

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Yeah, you can use weak or unknowable, so two options to resolve it.

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And what's the difference between these two?

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Because weak is an optional one and unknowable you guarantee the app that it's,

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you have, it's like an unfortunate in others.

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Right, right.

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And that's interesting.

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So when we're working with this, right?

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So I see that almost no one uses a null.

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Do you know any scenario where you can actually use a null and be locally safe with that? questions?

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Well, I think you can use it another way like when you have a reference between one,

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just one class, like when you have a protocol inside in a cell,

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for example, and the view controller has the table view.

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You know that this protocol just will exist in this case because the cell,

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it's just in there in this view controller.

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It's not being used in anyone, in some somewhere, sorry.

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And so you can use anodes in this case, that would be a problem.

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Right.

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Okay.

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Yeah.

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Yeah.

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Interesting.

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So let's then jump to next one with the, just maybe about the, you know, coming back to the closures.

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So we have the closures, right?

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And they have some specific, I would say, working with the references.

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When we're working with the references inside the closures, can you tell what we need to be aware of?

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You need to be aware of the routine cycle that you want to know?

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I don't know if I understood everything, sorry.

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No, no, I mean, that's one thing.

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I agree.

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But for inside the closures, how we can be safe with this kind of routine cycles,

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what we should you can use wix itself as i as we said and guide let's to okay the the view

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all right and then so for closures sometimes

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when i'm using it for the functions from time to time

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and it has a big different syntaxes in the you know

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in the function name sometimes called escaping sometimes it's not escaping

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can you tell me the difference between this what's what's the

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point to put this yeah i already use it it's before of course

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but yeah i can't exactly remember

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that as i think escape as i can remember escaping i

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think you can pass a code of block to be be executing in the in the order

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when they the user would be call this function with the closer

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so So you have a complexion one that I can remember, sorry, but yeah, my knowledge about that, it's not good.

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It's not very close by the answer, but yet.

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Okay.

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Got it.

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Got it.

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Right.

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And then, so the closures, uh, really, you know, they are, they are very powerful, right?

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But is there, do you see, do you think it's a best practice to use closures as a parameters for functions today?

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you know in a protocol oriented object it would be better Right.

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But in the case when you need to, let's say, when I have a function and after that function,

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after, you know, finished, we want to call another function.

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Yeah, you can use a guarantee sequence.

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That's right.

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As we use, you know, with closures as a parameter, it's usually because when it's the parameter, we're calling it callback or, you know, completion block.

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And then we're calling it and then putting some piece of code there to be called after the function or, you know, after we complete it.

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Yeah.

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Today, I think it would be better using the triassincurate in this case.

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Right.

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Yeah.

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Good, good.

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Assignuate is a modern way for threading, right?

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And working with the threads.

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Do you know any old style way for working with threads?

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What do we have to use in a normal multi -threading without a sync weight?

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Dispatch queries, you mean?

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Yeah, for example, dispatch queries, something else?

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Yeah, dispatch queries, as you said, the completions in some case should be...

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I'm specifically about, you know, working in the multi - Dispatch group.

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Dispatch group.

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But that is just a part of GCD.

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So we have a GCD.

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We have a Syncquate.

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Something else?

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Do you know about something else?

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No, that I can't remember.

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Sorry.

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Have you heard about the operation queues?

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Oh, operation queues.

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Yes, but I never worked at Zwift.

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Yeah, but I have...

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Right, right.

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So for.. for these things to work.

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So this AsyncAway and GTD in general, we're saying that it's multi -threading, right?

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In our project.

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But does it really clear multi -thread in our apps?

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Or, I mean, how does it work that we can do things on different threads?

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If we have, you know, iPhones with adjusted one or two core, actual physical core, I mean, do you know how

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but i can create you know hundreds of threads i can create hundreds of calls

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and gcd different priorities

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or how does it work do you know general what what

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does it mean for us this multi -threading for the apps is it the same as nvidia you know

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when you have a thousand of separate threads where each works separately

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or it works differently for us let me see we have a concurrence and also, oh my gosh, I forgot the...

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That was my thing.

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Yeah.

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And you can create, you can work with that.

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If you create other, like you said, it would be just to be more organized to us or just to,

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but it's not, we work like in really so many different strategies.

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It would be more for organize the codes for, we have this, these two ways to, to, to work with it at the,

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the simultaneous and the asynchronous ones.

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Yeah.

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I don't know if you, you want to know about it.

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Sorry.

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Yeah.

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I mean, okay.

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It's everything, everything fine.

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Let's then talk about, that's a good thing.

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So we talked about the threats and concurrency, you know, how things works.

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And the part of this, you talked about the async way, how this works.

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But part of this topic is also so -called actors.

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Do you know what is actors?

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How do we work with this actors thing?

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Yeah, you mean these annotations that you...

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Yeah, for example, annotations.

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Yeah, you're using some annotations to put this whole object or just the functions in a specific branch,

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like a main actor.

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okay but uh do you know

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that we can actually create actor ourselves yeah you can create

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actors like this yeah we have class we have structure

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and then we have actor as a you know a keyword

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we can create actor something do you know what what what

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it give us to create such in such a way for example some class user manager

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or something like this yeah actors uh as i said to change the block

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or the objects and its markets that it would be due in a...

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Well, it's markets the code or the function on a code block to do something that you want,

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that you like a main actor, it would be that you mark the code block to be executed in the the main QE,

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let you create an actor for other...

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Like at this table, you would be due that the code of blocker is the, the, the, the, the stable from other, from the, the current app.

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Okay.

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But, but I'm, I'm saying that, so you're saying about the marking something as attribute like main actor or something like that for the class, right?

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Mm -hmm.

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Or, or property in the class.

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Yeah.

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What I'm saying that we can create actor as, you know, as you, for example, you have a, let's say,

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network manager or user manager that manages users.

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You have a class, user manager, something, something.

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In the same way, we can create actor, user manager, something, something.

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Do you know what would be the difference or what is the scenarios when would be nice to create actors such?

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yeah honestly no i never worked with this okay type of actor got it got it

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and uh probably last thing about um uh just in this you know topic

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so we have so -called thing solid have you heard about the solid yeah

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and there is some you know something called the dependency injection

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just interesting how you would do it in the project without any with

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or without frameworks If you have worked with some frameworks, just tell me with which, how you worked and the scenario when you don't have any frameworks, how you would do it.

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Yeah, I have worked with Swinject,

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but also with products without Swinject and we create our own factories.

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Sometimes builders are necessary to inject some dependencies too

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and sometimes just it's a it's a complex subject you know

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like just an in meets with others it's already an injection dependence

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so yeah all right yes yes i mean cool framework right

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let's wrap up with this part yeah you've been really great

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for this part i i have just maybe a few comments

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so just about the first question you remember was about the inheritance in the suite

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and can we inherit multiple classes and there is might be some misunderstanding, but the thing just to, you know, be clear here in the iOS,

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in the Swift and Objective -C, we don't have multiple class inheritance.

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Just as example, as just I said it, so we have class A, then you have inheritance from class B, then comma inheritance class C, you can't do it.

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So that's why we're using product protocols, that's why we're using, but we can, we can use like simulated in a way.

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So in a protocol oriented programming, when you have multiple protocols, we have, you know, infinite amount of protocols that we can implement, but it's a different one, right?

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So between inheritance and implementation or something, but in a way we can simulate it because what we can do,

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we can extend the protocol and then do default implementation for each function, right?

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Of the protocol, for example.

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That meaning that we have a default implementation for functions.

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And whoever inherits or implements these protocols actually has default implementation for functions.

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Same way as it would have during the inheritance of these functions from another class.

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You see what I mean, right?

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So this is the trick where we could use to have

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this kind of multiple inheritance doesn't mean it's always need to be in place, doesn't mean it's always good, but just the fact that we don't have multiple inheritance,

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but we can simulate it in a way with a protocol

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or in the programming with extending it and giving it default implementation for the functions.

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Right, the other one about the actors.

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So basically just my comment that, you know, check it out, how it works.

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It's something that now on the, you know, on the top of discussions, where to use it, where not to use it.

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Yeah, I would say it's helpful for some specific group of tasks.

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So the difference would be that the actors makes your data inside secure for threats,

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for concurrency, but it has some drawbacks or I mean, it has some tricks.

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So you need to be aware of something there.

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So it doesn't mean that you guarantee that everything that runs inside the actors, threat safe.

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If something comes from outside, if you have some parameters and functions that comes from outside, there is no thread safe anymore,

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even though it works inside the actors.

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But whatever inside class as property in the class, as some variable, I mean, in the class, some counters,

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some other classes, it's safe.

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So that's just cool to know.

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And for scenarios like maybe network manager, maybe user manager, maybe some credentials or other parts

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when you need threat safes that's a good idea to create actor

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but yeah it's it has some definition it has some behavior

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so you know the part about the part about

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that in general about the actors is set right

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that we have this kind of main actors

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and to run everything even there you could be a bit

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more district this descriptive in a way why we need it

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or how it help us yes i didn't ask it

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but just you can just tell it

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that okay we have this kind of main actors it's it

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helps us to run everything on the main thread on the main queue

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and we save there so that's really helpful

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because before we needed to run in dispatch queue main async everywhere for example to guarantee

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that this code works and now if you just mark it with the main actor.

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And then in most scenarios, it runs on the main queue.

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Again, there is some, you know, some scenarios when something could go wrong, but it's a bit harder scenarios, not just a normal when you're just calling some functions or,

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you know, changing some variables.

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That should be pretty, pretty fine.

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Right.

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That's pretty much it.

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Otherwise, yep, we took clear.

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Was something, ah, yeah, the closures.

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I asked you about the closures, right?

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It's a class as a reference type of course there are closures

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because you can pass them I asked if the closures value type or reference type remember this?

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Yeah I remember this but I didn't understood.

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Yeah yeah it might be again misrepresenting in a way so just saying that the closures

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reference types

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so that's why we can pass them in the parameters of

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functions that's why we can in general working with them in such way that we can call them afterwards.

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Same for escaping, non -escaping.

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You answered in a way for this, but the clear answer would be that escaping closures,

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they basically escaping current context, meaning you have a function that returns something.

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So escaping closures can be called after function returned.

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And non -escaping will be always called, you know, just sequent.

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It's called and then something returned.

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So in the moment when you have some thread work or some async work, where you're calling this kind of closure,

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the compiler, it has compiler check.

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Compiler will tell you to put escaping there because you will call this closure afterwards,

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after the function finished, just to cover up this topic.

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Right.

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Yeah, that's pretty much it.

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Let's now jump to interesting part, practical part.

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So I will send to the chat some part of the codes and if it's fine to you, you can maybe share your screen with the playground.

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If you can just start it.

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I've sent some code in the chat.

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If you see it.

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Nice.

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Yeah.

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Just pass it there and then let's discuss.

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Right.

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So you can maybe, yeah, just ignore it.

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It's fine.

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So you can maybe just increase the font size here.

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Increase font size?

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Yeah, just or comment plus maybe.

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Yep.

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Nice.

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Right.

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So let's just ignore this.

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Let's just thread safe checks.

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It's fine.

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But in general, let's just discuss this code.

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How do you feel about this code?

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Do you see any problems with this code?

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what kind of followers you see?

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What would you improve?

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Yeah, I think here I will check in this way.

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You can say in this case, if they're this way, you pass the data.

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What do you...

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You need this one too.

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Right.

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And you need to put a return to avoid call tries that I can see.

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Right.

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What do you think about the first two constants that we have in the class?

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First constants?

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Ah, yeah.

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Do you have any comments about this?

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You'd say that if it's a charge,

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would it be uh states it needed to be no it's needed to be staged but not

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Same day both.

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That's fine.

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I mean, you don't need to mark anything for now.

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Let's discuss, you know, just a singleton here.

491

So you have a shared singleton, right, for network manager?

492

Yeah.

493

Any comments on that?

494

Do you feel it's fine?

495

I think we need to create and initialize it to

496

that's assumed that it would be just one

497

and in it but yeah I can't see any problems here sorry I think okay for the session

498

Is it fine to have such a session as shared one here?

499

Just use the shared one?

500

Yeah, I don't see any problems.

501

Okay.

502

Right.

503

So if today you would do something like that, let's say you need to load data, would you do it like this kind of function?

504

Or would you do it differently?

505

If today I do, I think I wouldn't create a network chart.

506

I will create a final class with a protocol.

507

Okay.

508

So why would you need the protocol?

509

No, with some get, the other ones, like put and everything else.

510

and the load data would be my network would be in the my network service

511

I think but the way it implemented do you like it the way the implementation way of this function

512

or you would change it to something else for the function

513

you mean yeah for the function itself the searching yeah

514

so you basically need to load data right by url some some url

515

that coming it could be let's say images whatever

516

and you have some urls

517

and then updates you got it you need to do something

518

with this data would you use function like this for your real project

519

or how we would do it no in my real products of course not because it's a it's a simple function.

520

It just puts an URL.

521

You don't know if the URL is a UTF string.

522

Also, sometimes you need methods,

523

parameters, and I think who else to do this one.

524

But for a simple function, I don't see in big project in a huge problem, you know?

525

Okay.

526

Yes.

527

Right.

528

I mean, there could be, of course, different, different way for improvements to this function.

529

One of the way would be using a sync way instead of completion blocks, right?

530

So would you use the, how you, you know, today in your work or in your pet project,

531

why would you prefer using the completion blocks for such functions?

532

No, I prefer using a SyncAway.

533

A SyncAway, yeah.

534

So this could be also mentioned in a way, but I know that you know it.

535

So just to be clear here.

536

You see inside the function, there are multiple completions, right?

537

Mm -hmm.

538

And multiple places.

539

Do you know any way to move this completion just in one place?

540

That guarantees that it's always called?

541

Yeah, you can like put that. So it's like that.

542

I got it.

543

Yeah, that could be one way.

544

Let's say that inside this task, we have more if else's or garbs inside.

545

For example, when you need to parse do so or do something else. So sorry?

546

Yeah.

547

It's fine.

548

Sorry.

549

Can you repeat, please?

550

Yeah.

551

So let's assume that you have multiple if -else's inside this task.

552

Yeah.

553

Right?

554

So when you need to call...

555

Like it.

556

Yeah.

557

Like here.

558

So let's leave this scenario when you have this.

559

But do you know any way to still call just...

560

you know this completion just once inside the function but without changing the

561

signature without changing yes some way some blog of code

562

that will be guaranteed then there is guarantee

563

that it will be executed before function is returned when everything is finished it will be executed.

564

Yeah, I just want one.

565

Have you heard about that defer?

566

Defer?

567

Yes.

568

Uh -huh, you know what?

569

Let's see how we would do it.

570

I already know about in -out and defer,

571

but I can't apply in this situation.

572

No, no, it's fine fine just so you know

573

that in some scenarios

574

when you need to return after all the code is you know run best practice to use return

575

or defer it's just you know as just a simple block that will be called

576

um after function returned that could be better

577

if you're using still such the completions

578

when you need to you know do this but

579

and how are you use here yeah yeah exactly here you would return here

580

but you need to provide then you create before defer a variable

581

that holds inside possibly data so you would as you would work with the data it would be nil or something

582

And if you would have an error as well in the part of the completion block, then you would need to do the same.

583

So it's either exists or by default just an ilk and it will be executed after this task finished.

584

Right.

585

And then let's just maybe check one more example.

586

Yeah.

587

Just wondering, have you worked with the SwiftUI?

588

Yes, my main background is SwiftUIKit.

589

But have you really worked with SwiftUI in a way?

590

Yeah, in just views.

591

Okay, got it.

592

Let's maybe combine it.

593

Okay, so UIKit you said, right.

594

Gonna be simple example, too simple for you.

595

Just drop it to you.

596

This one?

597

Yep.

598

Any problems here?

599

Any problems?

600

Yeah.

601

We have chains in global QA.

602

It's what's being the main QA and also it would be better

603

if you have thread safe

604

or thread safe nor everything cycle safe to to view i would say

605

that you don't need it here you can

606

because you can assume that's it just

607

but yeah i prefer using every time for safety

608

but then what would be

609

if you hear instead of async main async will use main sync would be any difference yeah

610

when you use sync you are like stuck the the codes the the view

611

and and the codes will would be as acute

612

so the layout it's it's what's stuck in the the view

613

but is it is it always true that it will be stuck.

614

Oh, it's true?

615

Yeah, I mean, why even this sync exists then?

616

So, can we use it sometimes?

617

Or is it always?

618

Yeah, if you have a very important info or you need like

619

code to be executing in the same type that you want, it would be better use sync.

620

Okay.

621

Right.

622

But let's say today, can you, can you maybe change this code in a way

623

that you don't need to use the async dispatch queue main async at all?

624

What we should change here?

625

So we know that this function called of the data loaded, right?

626

So inside, let's say some background queue where we did some requests.

627

How you can change it. So.

628

Because I would say that we don't need to use this dispatch code main thing at all.

629

Yeah, because you mean that it's...

630

If the functions wouldn't be called from an API, you mean?

631

Like, let's say you're using...

632

In today's code, you have some background work, right?

633

You have background request.

634

And then you have such view controller with this kind of load data.

635

How to change this code so you don't need to use dispatch queue main async.

636

So it's always executed on the main.

637

Because, you know, dispatch queue main async just creates this kind of doom effect, like spacing, you know, you just wrapped up it to some part of code.

638

You mean like put some main actor here? For example.

639

Part of here?

640

Okay, interesting, yes.

641

Right, and the interesting question would be, does view controller here in the class view controller,

642

is it main actor or not?

643

It can be, but in this case, no. It's just the function.

644

If you didn't put it here, yeah.

645

So if it's just like that.

646

Yeah, it's just like

647

that just this code block is all being the main actor

648

i got it i got it yeah i mean then we can wrap up

649

so just for for comment for this one would be nice to know for you

650

that in this example view controller is main actor really yeah that's the interesting thing to remember

651

because if you go inside UIViewController, if you open it, somehow in your project inside,

652

you will see that in today's iOS development, all the UIViewControllers, all the UIViews,

653

they are inherent from or they have main actor basically.

654

So all your views, all your controllers, if they are part of the UIViewController, then they are by default,

655

they have main actor, meaning you don't need to put main actor at all.

656

It will always run this function on the main.

657

So the only thing that you would need to do to be sure that your changes...

658

If you're using async await, nothing you need to do.

659

It becomes hard.

660

Yeah, absolutely.

661

So you'll just call it then because actors and async await knows how to switch the context,

662

knows that this part of code should be run on the background and this part of code.

663

Now, you know, returning back from the context to this actor and running this part of code here.

664

But that's purely safe.

665

The only moment when you need to put these kind of marks, main actors, when you have your personal classes, like some view models, you know, something like that.

666

Yeah, I understood.

667

So then you, of course, need to think, should you put it there or not?

668

Usually, yes if you do something related to view you just put main actor on top of the class

669

but now in the modern iOS I think that comes with a new release

670

all the classes if I remember correctly will be by default

671

everything will be by default main actor as it's supposed to be all the properties

672

and you can turn it off for some functions if you need very nice I didn't know about it Yeah, so it's interesting.

673

Yeah, I think it's useful to remember for your code.

674

Yeah, very useful.

675

If you just put it as, sometimes people are putting dispatch queue main as sync or running main actors for no reason, basically.

676

Because every time you're putting it to the code, meaning that you're just delaying it for some amount of, you know, nanoseconds, whenever, this part of code.

677

At the same time, it could be executed instantly.

678

And sometimes it affects your, it could affect your animation or some presentation, you know, in a weird way.

679

Instead of being a smooth, it could just be a little bit delayed and then presented for no reason.

680

When you can actually just, yeah, you know, use it.

681

To remove it, yeah.

682

Yeah.

683

Let's wrap up in general, Ramiro.

684

I think we did a great job.

685

So how do you feel about the...

686

running through this interview?

687

Was it hard for you?

688

Was it easy for you?

689

Yeah, it was hard to me.

690

Now I know that I need to study some points.

691

I have some lack of knowledge.

692

But it would be very nice to me to see what they want for me

693

and what I need to study more and I did some notes that you told to me.

694

Yep, sure.

695

You can always, if you have some questions or something,

696

I can reconcile what was the problem, what was the questions.

697

But in general, I think it was a really good session.

698

It's very different for interviews in Brazil, you know?

699

Yeah, yeah, it's very different because in Brazil,

700

they wouldn't know more about the real job you know like uh

701

and you this interviewer knew about the the knowledge of the

702

the the the the deep knowledge of the swift was very nice to to to have this interview thank you

703

so much yes thank you i i should say that all the all the interviews,

704

all the how it behaves, it really depends on the company, right, on the situation, because usually when we're interviewing someone to the company,

705

we're not just interviewing some random person to random position, there is actual position actual team,

706

actual expectation from this person and that gives more context usually to the

707

to the interview here on the mock interview on the other

708

side we have to go generally about things you know just pick more general topics of course

709

if you would interview to you know some audio company we

710

would talk about the audio you know core core core kids you know some

711

very different frameworks audio frameworks

712

and how you would work with this it's really depends to become where you're going

713

but i think so that that was a great

714

going through all these topics sections so i hope it was useful for you and uh

715

that's that's pretty much it thank you very much thank you for your time yes bye

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Vocabulary and speaking notes for this lesson

This C1 speaking lesson is built on the video “Mastering iOS Development: Mock Interview with Ramiro Neto”. The speaker keeps coming back to these words: function, actor, code, main. This video has 715 sentences and 7063 words to shadow. The speech runs for 52:14. The speaker talks at a steady 135 words per minute, a comfortable pace for shadowing. 87% of the words are among the 3,000 most common in English; the rest is worth studying before you start. 111 of its 715 sentences are questions, so it is good practice for question intonation and short answers.

Key vocabulary in this video

The 15 most advanced words in the video, with pronunciation and meaning:

Word	Pronunciation	Meaning
asynchronous adjective	/eɪˈsɪŋ.kɹə.nəs/	Not synchronous; occurring at different times.
dispatch verb	/dɪˈspæt͡ʃ/	To send (a shipment) with promptness.
queue noun	/kju/	A line of people, vehicles or other objects, usually one to be dealt with in sequence (i.e., the one at the front end is dealt with first, the one behind is…
inherit verb	/ɪnˈhɛɹɪt/	To receive (property, a title, etc.), by legal succession or bequest, usually after the previous owner's death.
inheritance noun	/ɪnˈhɛɹɪtəns/	The passing of title to an estate upon death.
execute verb	/ˈɛksɪˌkjuːt/	To kill, especially as punishment for a capital crime.
sync noun	/sɪŋk/	Harmony.
parameter noun	/pəˈɹæm.ə.tɚ/	A value kept constant during an experiment, equation, calculation, or similar, but varied over other versions of the experiment, equation, calculation, etc.
defer verb	/dɪˈfɜː/	To delay or postpone.
comma noun	/ˈkɒmə/	The punctuation mark ⟨,⟩ used to indicate a set of parts of a sentence or between elements of a list.
annotation noun	/ˌæn.əˈteɪ.ʃən/	A critical or explanatory commentary or analysis.
compiler noun	/kəmˈpaɪlɚ/	One who compiles.
query noun	/ˈkwɪɹ.i/	A question, an inquiry (US), an enquiry (UK).
mock verb	/mɑk/	To mimic, to simulate.
agile adjective	/ˈæd͡ʒ.aɪl/	Having the faculty of quick motion in the limbs; apt or ready to move; loose-jointed.

Phrasal verbs you will hear

Word	Meaning
go through verb	To travel from one end of something to the other.
wrap up verb	To cover or enclose (something) by folding and securing a covering entirely around it.
cover up verb	To conceal or disguise.
get back to verb	Return to (an activity)
run through verb	To summarise briefly.

Sentences worth repeating

Short, complete lines from the video that you can reuse in everyday conversation:

How do you find a balance in that?
Can you repeat the first synthesis, please?
How do you kind of sell it?
Can we inherit, let's say, two classes?
Do you feel it's fine?

Grammar in this video

The structures the speaker uses most, with the exact words from the video:

Structure	In the video
Conditional sentences if + clause, will/would + verb — a condition and its result	if today you would do · If the functions wouldn't be · if I remember correctly will be
Present perfect have/has + past participle — a past action that still matters now	have worked · I've seen · haven't taken
Passive voice be + past participle — the focus is on what happens, not who does it	be approved · is approved · be delivered

Pronunciation to watch

The speaker uses 78 contractions and reduced forms, such as don't, you're, I'm. Say them the short way, as you hear them.

The “th” sounds: smoothly /ˈsmuːðli/, synthesis /ˈsɪnθəsɪs/, algorithm /ˈælɡəɹɪðm̩/
The “sh” and “zh” sounds: annotation /ˌæn.əˈteɪ.ʃən/, injection /ɪnˈd͡ʒɛk.ʃən/, credential /kɹɪˈdɛnʃəl/, implication /ˌɪmpləˈkeɪʃən/, gosh /ɡɑːʃ/
Long words — get the stress right: asynchronous /eɪˈsɪŋ.kɹə.nəs/, inheritance /ɪnˈhɛɹɪtəns/, parameter /pəˈɹæm.ə.tɚ/, annotation /ˌæn.əˈteɪ.ʃən/, concurrency /kəŋˈkʌɹənsi/

How to practise with this video

Listen to the whole video once without speaking and note the words you do not know.
Shadow it sentence by sentence at normal speed, repeating each one until your rhythm matches the speaker.
Record yourself and compare with the original, paying attention to words like asynchronous, dispatch, queue.

What is the Shadowing Technique?

Shadowing is a science-backed language learning technique originally developed for professional interpreter training and popularized by polyglot Dr. Alexander Arguelles. The method is simple but powerful: you listen to native English audio and immediately repeat it out loud — like a shadow following the speaker with just a 1–2 second delay. Unlike passive listening or grammar drills, shadowing forces your brain and mouth muscles to simultaneously process and reproduce real speech patterns. Research shows it significantly improves pronunciation accuracy, intonation, rhythm, connected speech, listening comprehension, and speaking fluency — making it one of the most effective methods for IELTS Speaking preparation and real-world English communication.

Shadowing technique: read the full step-by-step guide →

Shadowing Practice: Mastering iOS Development: Mock Interview with Ramiro Neto - Learn English Speaking with Video

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Vocabulary and speaking notes for this lesson

Key vocabulary in this video

Phrasal verbs you will hear

Sentences worth repeating

Grammar in this video

Pronunciation to watch

How to practise with this video

What is the Shadowing Technique?