Message::Passing::Filter::All - Filter all messages out.
This filter just removes all messages, not passing any through.
You would normally never want to use this, but it can be useful for testing occasionally.
Universally returns undef
This module exists due to the wonderful people at Suretec Systems Ltd. <http://www.suretecsystems.com/> who sponsored its development for its VoIP division called SureVoIP <http://www.surevoip.co.uk/> for use with the SureVoIP API - <http://www.surevoip.co.uk/support/wiki/api_documentation>