Provides safe access to descendent object members with parents that may or may not be null. This applies to objects as well as functions. For example, consider an object reference with three levels such as a.b.c. Testing for the existence of c would previously require nesting said test inside a test for b. This change allows you to test for c directly without an error being thrown when b is null.
Optional Chaining reached Stage 3 at the July 2019 TC39 meeting.
Docs: https://v8.dev/features/optional-chaining https://docs.google.com/document/d/1k7WuOEU6Bi7WwL5sHFLthxS7_jkG3ao3NsbFJ5DNwtQ/edit
Explainers: https://v8.dev/features/optional-chaining https://docs.google.com/document/d/1k7WuOEU6Bi7WwL5sHFLthxS7_jkG3ao3NsbFJ5DNwtQ/edit https://github.com/tc39/proposal-optional-chaining