JavaScript: typeof null = "object"?!PRO

A 1995 bug that can never be fixed. Check null directly, and arrays with Array.isArray().

// typeof null = "object" ?! — a bug from the first JavaScript (1995) that can never be fixed.
console.log(typeof null);          // "object" ?!
console.log(typeof undefined);     // "undefined"
console.log(typeof []);            // "object" too ?!

// Fix: check null directly, and arrays with Array.isArray
const x = null;
console.log(x === null);           // true ✓
console.log(Array.isArray([]));    // true ✓

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