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We'll come back in this lesson and continuing from our previous one we're going to talk about comments

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I'm in the process I'm going to explain some important aspects of how a compiler works.

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Let's go back to court in here.

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This is the app that all the projects have been working on and it only has a one file called the main

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that m.

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It's a little bit different than the dot and that you have in Iowa is projects that is connected to

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a dot h in here there's only one file and Devey that the wrong application works.

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We pressed the bill then run it goes through this file line by line.

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It goes from one line to another one to another one to another one it goes through the entire file and

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compares this whole thing to understand what it should do.

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That is essentially the role of a compiler not obviously obvious for earlier on about programming languages

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you can't just type whatever you like in here.

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It has to follow the rules of that particular programming language.

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However you can add comments if you just want to write something that is a note for you or if it's not

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for a colleague that you want them you want to pass on.

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So the way you're doing it is putting two forward slashes and this is a Carmens.

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Here you can write whatever you like.

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You can make the spelling mistakes and you can write about your code or something you remember.

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So for instance if I'm going along this code then I'm telling you that this and Aslaug is the code that

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helps us print.

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You can't just come in here and say this is the pre-install or if you want to you can just write here.

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I didn't quite get it.

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Let's review some parts I can type at some point.

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So it essentially is a way for you to write your own comments in real life examples and once you have

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a little bit more experience you obviously don't write this kind of comments you write comments for

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colleagues or people who might be reading your code down.

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That's right.

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Or things that you know you know that you have to revert back to them at some point.

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You might write something like that.

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It is not working properly review that Dox or you might write something such as this is the main preens

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method are reviewing it in what every class or something that makes sense to your colleagues.

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But for now you can write your own you know comments in here throughout your code.

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So when you go back to it it makes more sense for me however I'm going to remove everything that said

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comments.

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Obviously not that I should like and I'm going to remove all of these that line so I'm going to try

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to keep the quote minimal so it's not overwhelming for you guys but for you if you want you can write

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your own comments in here.

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So one way of writing comment was using two forward slashes comments Carmens the two watts slashes and

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there is another way if you want to write a longer piece of code and that is forward the slash the star

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and then you close it with a star for the slash.

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And here you can write multiple lines with many different things in them.

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So it will be entirely ignored by the compiler.

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So like I said when you press the bill down wrong the compiler goes in line by line by line but whenever

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it finds this sign to forego other slashes it completely ignores that line whenever it finds this line.

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It searches for the corresponding closing bracket and says let's ignore this entire piece and then move

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on to the next line and that's how the compiler essentially goes through your code and tries to interpret

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it.

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So whenever you want to put comments you can just go in here and say Here I want to say something and

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you can close it like this.

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Of course for one line it doesn't really make sense that we use this method.

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But if it was more than one line you could just add it like that and the compiler will know to ignore

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this while we are here and this isn't really as important but they have noticed people asking me how

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to show the line numbers.

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You go to Mexico to preferences in the Preferences you go to text anything on the very first thing up

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there is line numbers.

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So they exclude preferences text anything line numbers it will show you the number of the lines.

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Most usually you need to know the number of the lines but you know I kind of like to keep it in here.

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So with that in mind now that we know how to add comments to our call let's move on to our next lesson.