The Universal Fallback

The NaN/Null Predator

We've used || for falsy values and ?? for nullish values. But what if a value is NaN (falsy) but not nullish? ?? will not catch NaN!

A "Universal Fallback" chains these operators to ensure that no matter what goes wrong (null, undefined, or a failed math operation resulting in NaN), you always return a valid number.

The Assignment

Your function receives a parameter val.

1. If val is strictly null or undefined, return the number 0.
2. If val is a NaN result, return the number 0.
3. Use a single logical expression (no if statements) combining ?? and || to handle all three safely.