Inverse of required and equal

[JonasFovea]

Hi, I've just had a look over the examples, and stumbled about the fact that you can validate for Some, but not None.
Maybe that's something one would want to have.
Similarly, to check if a value is unequal can be useful in some cases.

[JonasFovea]

With equal I mean the inner equality check like with the length.

However having a general equality or inequality check for a specific value would be beneficial too.