How to use [neq]

The reference page of neq has its arguments, constraints and declaration.

[neq] is the not equal “operator” in Magic, and it requires two arguments, both of which will be evaluated as potential signals - And the result of evaluating [neq] will only be true if the values of these two arguments are not the same.

.src:int:5
neq
   get-value:x:@.src
   .:int:5