This is really interesting. The case pointed out in Ex.3 is pretty hilarious:
(from the bash manual)
The ERR trap [same rules as set -e] is not executed if the
failed command is part of the command list immediately following
a while or until keyword, part of the test in an if statement,
part of a command executed in a && or || list except the command
following the final && or || [...]
I like cabal because I can read & write messages when I'm offline or there's no internet. It's also nice because I can start a private chat room for my friends without anyone needing to host and maintain any servers or infrastructure.
(from the bash manual)