Nullish Coalescing Operator in JS

Thanks to Shanson I learned a new JavaScript operator: the Nullish Coalescing Operator ??

It it like OR || but it returns the “default” value you want to assign, where the OR operator would not return the undefined or null value, but the other.

Example

const myAge = 0;
myAge ?? 10
→ 0
// this returns 0

myAge || 10
→ 10
// this returns 10 because 0 in JavaScript is falsey

// The best way to spell out how this operator works is with this ternary:
myAge === null || myAge === undefined ? 10 : myAge

This operator is useful when dealing with falsey values that may not behave the way we intend, for our business logic, in a function.