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So I come back again in these three lessons we are going to talk about of variables.

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How do we declare variables avoid the static and dynamic variables.

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How do we deal with annotations.

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And finally we learn interpellation for printing or converting diapers.

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So let's go to school and in here I'm going to make you let's make a new playground actually for this

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lesson for the next one I will do a new command tool.

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So Neo-Pagan all I'm going to call this one very bad is our playground.

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So variables to take out.

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So let's see how we do.

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These are four things essentially variables let's howl but otherwise inter relations and annotations.

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Let's see what do they mean.

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So for declaring any variable in sway if you have to use the term voucher or you have to use the term

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left and then immediately after either of those you come up with the name of your right.

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Imagine I want to integer somebody on my end.

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Now there are two ways of declaring this to be an integer.

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One of them is explicitly telling that there is going to be an int that is voicing column int and let's

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say that's going to be 5.

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And the other way is saying let my int 2 is 5.

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So in the first method you have explicitly used annotation to tell the compiler that this variable or

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is constant is off the typed integer in the second one.

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You have actually allowed it to defer from the value that you have initialized it from.

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My suggestion to you and anyone who is just starting with is always do it like this.

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So you know what you are doing.

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So if you're going to ever open a string let's say let's apply a string string that says Hello.

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So this would give you a lot more confidence at early stages.

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Of course you could also rely on the naming that you are using but a lot of time that naming will not

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be like this.

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So for instance you might have something called a username and then that doesn't necessarily tell you

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that it is of the type of string.

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It just tells you it is a variable.

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So I started a string and then I'm going to introduce an empty string for instance.

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At this point so so far we saw are three things we saw what are all variables.

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Variables are the values that you want them to change in Objective C terms you can imagine the value

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bet is something like N.S. a string y Let which is a constant is something like an S mutable string.

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It's about the mutability of the values of course.

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So the next thing you have to talk about is the annotations.

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How would they print these values.

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So I could go ahead and say print.

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And in my print I would say print my string.

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And that's something that you know you have seen before as well.

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So if I execute my play and art This one says hello and then that one says hello the way we expected

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it.

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But how would they print my integer.

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How would they do the formatting.

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Now for my thing in is a lot easier than what we used to do in Objective-C in Strief you would only

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do this you would say I want to get a strange result.

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I want to do an interpolation.

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Then you say for one of the slash privacy's practices in your practices you type whatever you're trying

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to get.

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In this case my ins and there you have it it prints five.

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So for instance I could say My aunt is as usual put a column and then do this little format and then

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say execute and it says my intice five any value would be essentially the same thing if not a variable

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might float of the type float to be three point five.

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Then I would say well print fantasies between the practice Zeitz I'm going to say sorry I'm going to

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say quotation marks for a string and then a forward slash and burn practices and my fruit and that's

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about that.

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So any value would be printed Similarly in here I would say my float is

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perfect.

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So now that we are here let's quickly talk about two very simple things that actually have one.

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So commenting is something you already saw it.

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It's exactly identical to what we had in Objective-C.

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So you do common things like that.

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And finally if you notice you don't need to put the semicolon at the end of your lines so you could

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optionally if you like to stick to the same programming format but more and more programming languages

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are going towards an era of their semicolon is not necessary anymore.

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Swift certainly doesn't need it.

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Cosmoline the new programming language for Android development doesn't need it.

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So you could just not have them and get used to the format that Swift is by default.

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And that's kind of the recommended way by Apple itself.

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So that's allotted for variables and Konstanz in interest.

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I actually recommend that before you go to the next lesson which is about the optionals just play around

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a little bit with these and get a sense of how they are trying to take one of the apps that you have

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within the past.

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One of the projects that we did earlier on and tried to come in here just the just a valuable part of

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it.

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So you get a sense of what could go wrong before we go to next lesson and we're going to talk about

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the options.

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So I see that.