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You HAVE to know the new question mark syntax in ES 2020

jadenconcord profile image Jaden Concord ・1 min read

I just discovered the Javascript feature that I have been waiting for in a video by FireShip.
You know how dangerous it is to not prevent an error to something like this,

function getDataFromClient(data){
  console.log(data.items.name);
}
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If the above were a node.js application, the client sent a response as an empty array, the server would simply cause an error and stop. Dangerous!
You could solve the problem like this

data.items && data.items.name
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but if you forget to do that it is super dangerous.

Now, in ES2020, there is a new feature that allows you to easily prevent this. It looks like this

data.items?.name
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Watch this video to know more about it.
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