[stringtemplate-interest] which ST errors are serious

[Brain, Jim]

If you have a listener concept in v4 and will pass the errors to the listener, it seems to me that someone who needs Exceptions can just throw the exception in the listener.

Is it common in systems to have a "conditional Exception system" like this, where the same conditions may or may not throw Exceptions depending on some configuration setting?  If so, I'm unfamiliar with it.  From a language perspective, I much prefer Exceptions either be "always" or "never", not "optional"

Jim