JuniorTheoryCommon

What does the program print?

JavaScript

const n = 0;
console.log(n || 10, n ?? 10);

10 0

Expecting ?? to replace 0 as well: ?? reacts only to null and undefined, and 0 is neither, so n ?? 10 gives 0.
Expecting || to keep 0: || returns its right side whenever the left side is falsy, and 0 is falsy, so n || 10 gives 10.

What does the program print if n is null instead of 0?
Which of the two operators would you use for a default count that may legitimately be 0?