Consistent Use of Exceptions

[Logan Ward]

The text interface for Magpie reports Exceptions to the user without exiting the program.

At the moment, this feature is mostly used for reporting syntax errors. It would be a lot more useful if most errors that can be corrected by the user (e.g. mistyping the name of the property to use as the class variable).

A few things that are in dire need of exception handling are:

• Setting the class variable
• Creating attributes
• Training / running models

[Logan Ward]

I've started removing the use throwing "Error" exceptions, which are the only kind not caught by the web interface.

Plus, the main way I use Magpie is using it with input scripts. In this case, throwing an "Error" is not that big of an issue. When running as a script, I want Magpie to stop execution for any exception/error/etc.