Yep. "Make invalid states unrepresentable" pairs well with "parse, don't validate"; the states that are valid for your business domain are (maybe) not the same

Yep. "Make invalid states unrepresentable" pairs well with "parse, don't validate"; the states that are valid for your business domain are (maybe) not the same as the states that are valid for your storage or wire format, so have different representations for these things.