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Now what do you do if you have a library where you can't install types as we did it for load Ash for

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example for a load Ash.

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Thankfully we had such a types package and as I mentioned for most third party libraries you have that

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but not necessarily for all or what if you have some other javascript code let's say in your index H

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html file you have some other script code which execute stare where you set some global variable global.

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This is set something like this where are you in the end.

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No.

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This will be a way lable globally as you know such variables added like this will be added to the global

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Window object and you want to utilize them from inside your types code.

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For example here if I want a console log global like this I get an error here in my idea and if I run

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TSC dash W to start copulation I also get an error here so it doesn't like that global thing even though

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we know that it will work because our next HMO file defines this global variable.

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And since we have defer on this script this script will be executed after this script down day Iran.

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In such cases you have no syntax a way lable in typescript and that is to declare command which you

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can use.

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You can declare certain variables for example to typescript you can say declare var global and tell

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typescript that for example this will be a string or that this is anything.

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This basically tells time don't worry it will exist it ever if we do is save this and I quit this compiler

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and use Web pig instead.

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We do see this output on our page because it's technically works and with declare war.

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We also tell typescript that does exists.

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Now I'm going to remove to stymie code here.

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But being aware of declare off does keyword of this command is important.

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It allows you to declare typescript features or variables where you know that they exist or let typescript

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know about packages global variables in general which types who can't know but where you as a developer

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know that they will be there.