Implementation of a conditional onEvent helper that guards the execution of the event with an alert dialog.
Implementation of onEventIf, a version of onEvent guarded by confirm().
H/t for this little innovation actually belongs to @shadowfiend. I'm
just taking credit for bringing it into the latest version of Lift. ;)
This is a bit late, but mailing list thread: https://groups.google.com/d/msg/liftweb/7vvVPmi53Kc/8Ko02NbJv38J