RequiredElementMissing is a subclass of Exception

[lgustafson]

The custom exception class RequiredElementMissing is raised when a required xml accessor is missing during parsing. It is currently a subclass of Exception, meaning that you can't use "rescue => e" to rescue an exception. Instead you'd have to directly rescue it or use "rescue Exception => e". My take is that this behavior is too surprising. It might be a good idea to at least document the difference in the rdocs.

[Empact]

I agree it should descend from StandardError or below, e.g. ArgumentError. If you make a pull request I'll happily include and release it.