Name: オブジェクト指向プログラミング in PYTHON - CS50 on Twitch, EP.33 (OBJECT-ORIENTED PROGRAMMING IN PYTHON - CS50 on Twitch, EP. 33)
Uploaded: 2021-01-14T10:25:06.000Z
Duration: 1 h 34 min 52 s
Description: VoiceTubeの動画で発音を聞きながら英語表現を覚えよう！学べる英語：

I'm joined today by Brian You, who has been upstream before.

Normally we build something from scratch.

But sometimes you do conceptual discussion.

So what we're talking about today, Today the topic is going to be object oriented programming, which is a programming paradigm that you'll find in a number of different languages today.

In particular, we're gonna be looking a python, though there's object oriented programming in languages like Java, for instance, and many other languages as well are beginning to use this paradigm, and it's quite popular in the programming world.

How does object oriented programming sort of compare and contrast to that?

So the style or programming paradigm CIA 50 talks about is this idea of what we might call imperative programming on what object oriented programming is.

It's a slightly different take where the focus is about trying to model Rhea World things as what we might call objects.

And those objects are gonna have two parts to them.

Objects might have some data associated with them, so you might have an object that represents, like a shopping item, for instance, in a store.

It has a price that might have an image associated with it.

For instance, on those objects can also have some code associated with them code that you can use to operate on or manipulate those objects.

A shopping item, for instance, might be some code some action that's associated with that particular object that you can use to make something happen.

Kind of taking it above the sort of bare metal of the computer a little bit more than something like See where you're literally coding instructions that kind of roughly mapped out the CPU talks in innocence.

It's often a feature of higher level programming languages that allow you to reason a little bit more abstractly you to organize code in particular ways.

We're gonna be able to write code that we probably could write in an imperative way.

You thinking CIA 50 style programming, but this is just going to offer a slightly different way of achieving the same thing, and it's ultimately going to allow for amore clean way of running certain types of code.

And then we'll be using python today, python being one of the more popular languages currently used.

But this is a paradigm that we see it all over the place and particularly job.

Some folks in our community might be familiar with Java, and John was a very, very object focused language where you literally everything has to be an object in Java.

If you're ready, I can switch over to computer if you want.

Guess on our trip to object oriented program.

So I have here a terminal window, and what I thought we do is dressed as a bit of an introduction to python.

Now, just go ahead and type python, which is going to open up a python interpreter.

I'm using python version 3.7, But any version three or later will probably be sufficient for the sorts of syntax that we're going to see today.

Andi In this python interpreter, I can begin to type valley the names of expressions or values, and I can see what they're equal to.

So the number I typed in the number 50 for instance, and what I get back from the Interpreter is OK.

That's obvious, cause I typed in the number 50 exactly, but you can type more complex expressions, right?

I could type an expression like 20 plus eight, and when I get back is not literally 20 plus eight.

But I get that expression which get the value in it to a value.

And that value in this case is 20 for instance.

And so this 28 here it's a number in particular, it's an integer, and if I type in the number 28 okay, its value is 28.

But there's a special function in python called type, which I can use if I say type 28 for instance, I can see all right, what is type And here we see the first instance of an object oriented programming word this word class class is going to tell me, sort of What type of information is this value?

The number 28 it's telling me, belongs to a class called int.

And so the way to think about this is 28 is an object.

It is a thing that exists is a value in python, and it belongs to a class.

What type of thing is 28 28 in this case is an end, and it happens to be one of the built in classes in python that I can use.

And in fact, any time you use an integer and python you're using, an object that is of this into class thrives on being more of a dynamic language.

It doesn't really have, technically speaking the same kinds of primitives that, like sea or even job, which Adam and Team didn't mention the chat.

Saying that he uses job doesn't primitive so that everything is an object I should clarify.

What I meant was everything is wrapped in an object.

For example, you can't write a main function without it being in a class.

But in Python there are There really isn't technically speaking, the idea of a primitive at least in terms of, you know, this is 32 32 bits and that's it.

It's essentially wrapped in some extra packaging.

Yeah, so all of the even this basic integer 28 has some data and code associated with it that a normal just a pure integer wooden house.

Oh, sure, I could do 28 dot numerator, for example, and say, uh, that didn't work.

I can say ex stopped numerator and okay, I get The numerator of 28 is just 28 the denominator of 28 is one, for instance.

And that's not something you could do if we just had the literal bits representing the number 28.

It only works because this variable X is what we might call an instance of the class, and when I say instance, I just mean that if it is a class than any time I have an object that belongs to that class that's going to be an instance of the class.

So X, in this case is an instance of this into class.

So, like class being the blueprint and then actual 28 is the physical thing.

Start if we want to take it, You know, into a physical analogy, the physical thing we use the blueprint to create or construct exactly.

Yeah, Andi And doesn't want the only class is built in the python.

If I have the string Hello, for instance, that equal to just call It s for strings, Right.

And if I take the type of s I see that s belongs to a class called Stir.

It is an instance of this class stir where stars restored short for string, for instance.

And there are all sorts of functions that we have that are associated with objects that air an instance of the stir class.

So, for instance, capitalizes one that just takes a string and capitalized the lower case H turned into a capital H, for example.

And so that's an example of yet another class that we have that's built into the python programming.

What you mentioned earlier is that these classes allow us to sort of tie this functionality to different data types to allow us to go after right functions.

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オブジェクト指向プログラミング in PYTHON - CS50 on Twitch, EP.33 (OBJECT-ORIENTED PROGRAMMING IN PYTHON - CS50 on Twitch, EP. 33)

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