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Now if we move on we get more options no unused locals no unused parameters no implicit returns.

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This helps you with code quality basically typescript will complain if you have certain unused variables

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and so on.

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So if we turn these free options on for example this option helps you with switch statements where you

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might forget the brake cured but if we turn these free options on what types will complain about is

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for example if you had a user named variable here locally in this function and you don't use it you

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see this has yellow squiggly lines because it's not an error really it's more like a warning or a hint.

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So if I compile here you see now however I do get an Arabic must have could only knows errors.

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And there we see the user name is declared but its value is never read because we made sure that we

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don't want unused local variables unused global variables so if I had something like app I.D. here are

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allowed though because typescript can't know if you may be need that globally defined value in a numbers

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script file so therefore this is allowed but in a function where there is no other place where you could

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needed typescript will complain now if you have unused code and that's generally a good idea allows

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you to strip out such unused code.

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Same goes for unused parameters if you would take a h here for one of course bind is broken now.

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But even if we pass this in this works.

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But now again TypeScript and therefore also the idea tells us that this is unused and indeed it is.

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So maybe you should remove it or start using it.

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So that's no unused parameters and no implicit returns means that we'll get an error if we have a function

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that sometimes returns something and sometimes it does not let's say we have another function at where

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we get two numbers number and and 2 is a number and of course we can return and 1 plus and 2 but let's

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say where for some reason checking if and 1 plus and 2 is greater than 0 because we only want to return

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if we have a result greater than zero and then we want to return to value.

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Otherwise we want to return nothing.

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We don't want a return.

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Well then we get a warning because of that extra setting with no implicit returns typescript detects

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that not all branches in this function lead to a return statement and because of our setting that's

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not allowed.

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We at least have to deliberately not return anything here by adding the return keyword just omitting

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it is not allowed here.

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It is allowed if you have a function that does not return anything.

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In no branch but if you have at least one case where your function does return something then you have

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to make sure you return something in all cases.

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And with that we're nearing the end of this contact walkthrough.

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We can ignore the module resolution here.

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All these options actually are pretty advanced that don't matter to us here don't matter to you in a

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lot of projects.

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Source map options allow you to tweak these source maps.

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We had a look at earlier so these translation files from javascript to typescript typically default

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settings should be fine here so if you don't know what you're changing and why you're doing it you typically

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don't need to change anything here.

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And regarding these experimental options I'll have a look at them specifically add experimental decorators

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later in the decorators module.

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This basically enabled certain features to be used in typescript which are really experimental where

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it's not sure if they will end up in JavaScript at sometime in the future and where you still might

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want to work with them.

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Then you explicitly have to tell typescript that you want to work with these features and you can do

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that with that configuration but again it will come back to that and therefore now we walked through

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this file.

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Lot of options you can set there and ask typescript grows.

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You typically also get more and more options.

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This.

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Therefore the official docs are of course always a great place to dive deeper and to make sure that

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you don't miss an interesting option that might help you in your project.