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function tryToReturnAnObject() {
	return
	{
		hello: "world"
	}
}
console.log(tryToReturnAnObject())

djD-REK

const tryToReturnAnObjectArrowFunction = () => {
	hello: "world"
}
console.log(tryToReturnAnObjectArrowFunction())

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const actuallyReturnAnObjectArrowFunction = () => ({
	hello: "world"
})
console.log(actuallyReturnAnObjectArrowFunction())

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function actuallyReturnAnObject() {
	return {
		hello: "world"
	}
}
console.log(actuallyReturnAnObject())

djD-REK

let failedMath = Math.sqrt(-37);
console.log(failedMath); // NaN
console.log(3 + failedMath); // NaN

let failedStringParse = parseInt("Operation Doomsday", 10);
console.log(failedStringParse); // NaN
console.log(3 * failedStringParse); // NaN

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let divisionByZero = 37 / 0;
console.log(divisionByZero); // Infinity

let divisionByEmptyString = 37 / "";
console.log(divisionByEmptyString); // Infinity

let divisionByFalsy = 37 / false;
console.log(divisionByFalsy); // Infinity

let zeroOverZero = 0 / 0;

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let myNaN = NaN; // or let myNan = Number.NaN
console.log(typeof myNaN); // "number"
console.log(myNaN == NaN); // false
console.log(myNaN === NaN); // false

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let variable = NaN; // or let variable = Number.NaN

// Check for NaN by checking for self-equality
console.log(variable != variable); // true
console.log(variable !== variable); // true

// NaN is the only value that is not equal to itself
let isNaN = (maybeNaN) => maybeNaN!=maybeNaN;
console.log(isNaN(variable)); // true

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let maybeNaN = NaN;
console.log(Number.isNaN(maybeNaN)); // true

maybeNaN = 3;
console.log(Number.isNaN(maybeNaN)); // false

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isNaN('hello world');        // true
Number.isNaN('hello world'); // false