The syntax to access the NaN property is:
Number.NaN
NaN is accessed using the Number class name.
Example: Using Number.NaN
// verify value is a number
function verify(x) {
if (isNaN(x)) {
return Number.NaN;
}
return x; // only return if number is not NaN
}
console.log(verify(5)); // 5
console.log(verify(5.45)); // 5.45
console.log(verify(Infinity)); // Infinity
console.log(verify("five")); // NaN
console.log(verify(undefined)); // NaN
console.log(verify([1, 2, 3, 4])); // NaN
Output
5 5.45 Infinity NaN NaN NaN
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