I begin to start using the validator and got confused of what is the design philosophy behind it.
1. There is an instance method validator_error that would be called if exist otherwise it would raise another exception. I believe this has to be mentioned in the documentation as otherwise, this exception would not be caught by anyone and it would be the ugly "server get in trouble" message, which is very scary but not the case. Just some data content error. If validator_error is defined, if will be called with the first parameter being the original function(the one that turbogears.expose supposed to be decorating). While the documentation said I can do whatever I want, I think it would be more natural to let the original function deal with it as this validator_error is a "centralized" function(sort of catch all) that is impossible to make meaningful error message/response. Would it be better to just have a convention that any exposed function that has validator enabled should expect one more argument "error=None" to indicate such condition and let it do its job there ?
