Events
- platform events
- user events
- <catch event="..."> used to catch platform and
user events
- <throw event="..."> used to throw user events
- <noinput>, <nomatch>, <help> and <error>
are shorthand notations for <catch event="...">
- event "subtyping" by common prefix: <catch
event="error"> matches error.a.user.specific.error as well as any other error.* events