MediumType Coercion💻 Output Question

Unary plus converts to number

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Hint

Unary + is the shortest coercion to number. undefined and non-numeric strings produce NaN.

What does this output?

console.log(+'');
console.log(+null);
console.log(+undefined);
console.log(+true);
console.log(+'3.14');

Correct Output

0
0
NaN
1
3.14

Why this output?

Explanation: +"" → 0. +null → 0. +undefined → NaN. +true → 1. +"3.14" → 3.14.

Key Insight: Unary + is the shortest coercion to number. undefined and non-numeric strings produce NaN.

More Type Coercion Output Questions

EasyPlus operator: string concat vs numeric add→MediumLoose equality edge cases with null→Easytypeof for common values→MediumTruthy and falsy — empty array and object are truthy→

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