Question why can GetComponent<Rigidbody>() be compared with Boolean values?

When we need to determine whether a rigidbody exists, we can use the following code:

Code (CSharp):

1.        if (GetComponent<Rigidbody>())
2.         {
3.          
4.         }
5.        
6.        
7.     if (GetComponent<Rigidbody>() == true)
8.         {
9.        
10.         }

GetComponent<Rigidbody> either returns null or Rigidbody, a Boolean value cannot be null, and also Boolean is value type while Rigidbody is reference type,

So, why does the compiler not report an error?

 

Because it defines a custom operator: https://docs.unity3d.com/ScriptReference/Object-operator_Object.html

But just use TryGetComponent instead. It's more performant in nearly all cases.