Optional Chaining in JavaScript [duplicate]

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This is currently a Stage 4 proposal you can check on the progress of it here:
https://github.com/tc39/proposal-optional-chaining

You can use the babel plugin today:
https://www.npmjs.com/package/babel-plugin-transform-optional-chaining

Update 11th January 2020:
Babel now supports optional chaining by default
https://babeljs.io/blog/2020/01/11/7.8.0

The Optional Chaining operator is spelled ?.. It may appear in three positions:

obj?.prop       // optional static property access
obj?.[expr]     // optional dynamic property access
func?.(...args) // optional function or method call

Notes:

In order to allow foo?.3:0 to be parsed as foo ? .3 : 0 (as required for backward compatibility), a simple lookahead is added at the level of the lexical grammar, so that the sequence of characters ?. is not interpreted as a single token in that situation (the ?. token must not be immediately followed by a decimal digit).

Also worth checking out:

https://github.com/tc39/proposal-nullish-coalescing

https://github.com/babel/babel/tree/master/packages/babel-plugin-proposal-nullish-coalescing-operator

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