Nullish coalescing for an object

TypeScript 3.7 brought the nullish coalescing operator: ??. On the left side of the operator is a variable or condition. On the right side is the result if the condition is null or undefined.

One use case for this operator is to check if a variable is set to define a default value.

The invocation of line 19 of myFunction does not have a second parameter. It causes the code to use the default value on line 8.