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Vikas Raj
Vikas Raj

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ECMASCRIPT: Optional Chaining | Stage 3

Optional chaining is at stage 3 πŸŽ‰πŸŽ‰. This one is my favourite. Soon will be available in TypeScript.

Optional Chaining for JavaScript

Status

ECMAScript proposal at stage 4 of the process.

Authors

Overview and motivation

When looking for a property value that's deep in a tree-like structure, one often has to check whether intermediate nodes exist:

var street = user.address && user.address.street;

Also, many API return either an object or null/undefined, and one may want to extract a property from the result only when it is not null:

var fooInput = myForm.querySelector('input[name=foo]')
var fooValue = fooInput ? fooInput.value : undefined

The Optional Chaining Operator allows a developer to handle many of those cases without repeating themselves and/or assigning intermediate results in temporary variables:

var street = user.
…

Discussion (4)

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drewtownchi profile image
Drew Town

Definitely one of the things I miss most from c# when I am using JavaScript. I'm glad to see it is making it into the language.

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khalyomede profile image
Khalyomede

This is definitively one of my most awaited features! Tons of checks will blow away!!

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chiangs profile image
Stephen E. Chiang

Finally, the Elvis operator is entering the building!

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numtostr profile image
Vikas Raj Author

I was so jealous of our iOS developers when I first saw them using optional chaining in Swift. And finally we'll be blessed with this feature. πŸ‘πŸ‘