Bits of .NET

|| operator treats 0 and ” as falsy. ?? only checks null/undefined.

Problem with ||:

const count = 0;
const display = count || 10;  // Returns 10 (wrong!)
// 0 is falsy, so falls back to 10

Solution with ??:

const count = 0;
const display = count ?? 10;  // Returns 0 (correct!)
// Only null/undefined triggers fallback

const name = '';
const userName = name ?? 'Guest';  // Returns '' (empty string is valid)

Use Cases: Default values for numbers, empty strings, false booleans where they’re valid values