Comparing NaN directly should be avoided

• COMPARE_NAN
• Error
• Medium
• No tags

This rule applies when NaN is directly compared.

In the JavaScript, direct comparison with NaN like x == NaN is always false.

Therefore, use isNaN function to determine whether a value is NaN.

Noncompliant Code Example

if (x == NaN) {
    x = 0; // COMPARE_NAN alarm
}

Compliant Code Example

if (isNaN(x)) {
    x = 0;
}

Version

This rule was introduced in DeepScan 1.0.0-alpha.

See

• isNaN()