Optional chaining ?. in javascript is a new feature introduced in ES2020. Optional chaining changes the way properties are accessed from deeply nested objects. It fixes the problem of having to do multiple null checks when accessing long chain of object properties in javascript.

JavaScript is a constantly evolving language. You can try out upcoming JavaScript features in Google Chrome. 

In this lesson, you will learn to turn on experimental JavaScript features by using chrome://flags. This will help you try proposed new features such as optional chaining in your browser's console.

Enable JavaScript Experimental Features in Chrome

Optional chaining enables safe access of properties of an object. It can be enabled in a Node app by using Babel preset-env.

Enable optional chaining in Node app by using Babel

Accessing a long chain of properties can be risky since one or more properties could be undefined or null. To be safe, we can use optional chaining when accessing long chain of properties. 

Access Long Chains of Properties with JavaScript Optional Chaining

JavaScript's optional chaining can be used to return prevent errors when accessing properties that do not exist. In order to return a useful value, we can combine optional chaining with null coalescing. 

Optional Chaining

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Course content (4 lessons)

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