include::../description.adoc[]

== Noncompliant Code Example

----
var a = double.NaN;

if (a == double.NaN) // Noncompliant; always false
{
  Console.WriteLine("a is not a number");  // this is dead code
}
if (a != double.NaN)  // Noncompliant; always true
{
  Console.WriteLine("a is not NaN"); // this statement is not necessarily true
}
----

== Compliant Solution

----
if (double.IsNaN(a)) 
{
  console.log("a is not a number");
}
----

include::../see.adoc[]