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So now that we learned a lot about middleware over the last lectures and we have a great way of debugging

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the app, let's go back to our app and let's think about running asynchronous code. In our demo project here,

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unlike any burger builder, we have no asynchronous tasks. Of course it's easy to create some,

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let's say that when storing a new result, we actually want to simulate that we also stored this on a

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server.

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Now we won't reach out to a server here because it doesn't matter but we can simply use set timeout to

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simulate that

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this simply takes a short period of time and we want to update the store after this is completed, let's

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say, the same for delete result.

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So essentially we want to create asynchronous code or actions here,

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now as I said, the reducer function has to run synchronously,

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you cannot add set timeout here because set timeout which as you know takes a function

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and then the timing,

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let's say two seconds, here you can't return the new state in there, it doesn't work,

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that's not how javascript works. This function only gets executed after two seconds, the switch statement

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will be done by then, you can't return in there.

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So typically what you would do, you would return a promise which calls resolve inside of set timeout

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after a certain period of time but your reducer just doesn't expect to get a promise.

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So there is just no way you can execute asynchronous code in here,

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there is a different way though. We can execute asynchronous code with the help of so-called action

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creators,

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so let's dive into action creators first before we then learn how we can utilize them to execute asynchronous

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code.