Eval() function return type for boolean expression

[ChrisRad89]

This is just a cosmetic thing, but maybe interesting for others...

The dialyzer is complaining about the eval function and a boolean expression. According to the docs, the return type is always a number(), which is not correct in the case of an boolean expression evaluation. There the return value is an atom(), 'true' or 'false'.
So is there a way to tell the eval function that we have an boolean return value? Or change the return value in general to any()?

[narrowtux]

probably should change it to any, since it could also be that a value from the scope is returned, which can really be anything.